Fix conda init problem and revert changes to conda base env

This MR reverts all changes to the conda base environment introduced in !14 (merged) (i.e. going back to 94c4248c) and provides an actual "fix" for the conda init error that currently (!) happens during conda base env container image builds.

In particular, the following

RUN /conda.sh conda init --system bash

is not a proper fix for

USER jovyan
RUN source ${CONDA_TARGET_DIR}/etc/profile.d/conda.sh && conda init bash

since it does not result in a properly initialized Bash shell for the Jovyan user

$ docker pull rz-container-registry00.rz.uni-kiel.de/cloudlab/base:v2022.09.22-conda
$ docker run -it --rm rz-container-registry00.rz.uni-kiel.de/cloudlab/base:v2022.09.22-conda bash
(base) jovyan@cloudlab:~$ conda --version
conda 4.14.0
(base) jovyan@cloudlab:~$ conda activate base
(base) jovyan@cloudlab:~$ 
(base) jovyan@cloudlab:~$ exit
$ docker pull rz-container-registry00.rz.uni-kiel.de/cloudlab/base:v2022.09.27-conda
$ docker run -it --rm rz-container-registry00.rz.uni-kiel.de/cloudlab/base:v2022.09.27-conda bash
jovyan@cloudlab:~$ conda --version
conda 22.9.0
jovyan@cloudlab:~$ conda activate base

CommandNotFoundError: Your shell has not been properly configured to use 'conda activate'.
To initialize your shell, run

    $ conda init <SHELL_NAME>

Currently supported shells are:
  - bash
  - fish
  - tcsh
  - xonsh
  - zsh
  - powershell

See 'conda init --help' for more information and options.

IMPORTANT: You may need to close and restart your shell after running 'conda init'.

because /etc/profile.d/conda.sh, which is generated via the conda init --system bash command is not loaded for interactive non-login shells. (Such as in a container environment, see also here.)

It seems, that the conda init error

Step 20/26 : RUN source ${CONDA_TARGET_DIR}/etc/profile.d/conda.sh && conda init bash
 ---> Running in b2bf2623e3f2
# >>>>>>>>>>>>>>>>>>>>>> ERROR REPORT <<<<<<<<<<<<<<<<<<<<<<
    Traceback (most recent call last):
      File "/miniconda3/lib/python3.9/site-packages/conda/exceptions.py", line 1129, in __call__
        return func(*args, **kwargs)
      File "/miniconda3/lib/python3.9/site-packages/conda/cli/main.py", line 86, in main_subshell
        exit_code = do_call(args, p)
      File "/miniconda3/lib/python3.9/site-packages/conda/cli/conda_argparse.py", line 93, in do_call
        return getattr(module, func_name)(args, parser)
      File "/miniconda3/lib/python3.9/site-packages/conda/cli/main_init.py", line 50, in execute
        return initialize(context.conda_prefix, selected_shells, for_user, args.system,
      File "/miniconda3/lib/python3.9/site-packages/conda/core/initialize.py", line 119, in initialize
        run_plan_elevated(plan2)
      File "/miniconda3/lib/python3.9/site-packages/conda/core/initialize.py", line 688, in run_plan_elevated
        result = subprocess_call(
      File "/miniconda3/lib/python3.9/site-packages/conda/gateways/subprocess.py", line 89, in subprocess_call
        process = Popen(
      File "/miniconda3/lib/python3.9/subprocess.py", line 951, in __init__
        self._execute_child(args, executable, preexec_fn, close_fds,
      File "/miniconda3/lib/python3.9/subprocess.py", line 1821, in _execute_child
        raise child_exception_type(errno_num, err_msg, err_filename)
    FileNotFoundError: [Errno 2] No such file or directory: 'sudo'
`$ /miniconda3/bin/conda init bash`
  environment variables:
                 CIO_TEST=<not set>
                CONDA_EXE=/miniconda3/bin/conda
         CONDA_PYTHON_EXE=/miniconda3/bin/python
               CONDA_ROOT=/miniconda3
              CONDA_SHLVL=0
         CONDA_TARGET_DIR=/miniconda3
           CURL_CA_BUNDLE=<not set>
                     PATH=/miniconda3/condabin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin
                          :/sbin:/bin
       REQUESTS_CA_BUNDLE=<not set>
            SSL_CERT_FILE=<not set>
     active environment : None
            shell level : 0
       user config file : /home/jovyan/.condarc
 populated config files : 
          conda version : 22.9.0
    conda-build version : not installed
         python version : 3.9.12.final.0
       virtual packages : __linux=5.4.0=0
                          __glibc=2.35=0
                          __unix=0=0
                          __archspec=1=x86_64
       base environment : /miniconda3  (read only)
      conda av data dir : /miniconda3/etc/conda
  conda av metadata url : None
           channel URLs : https://repo.anaconda.com/pkgs/main/linux-64
                          https://repo.anaconda.com/pkgs/main/noarch
                          https://repo.anaconda.com/pkgs/r/linux-64
                          https://repo.anaconda.com/pkgs/r/noarch
          package cache : /miniconda3/pkgs
                          /home/jovyan/.conda/pkgs
       envs directories : /home/jovyan/.conda/envs
                          /miniconda3/envs
               platform : linux-64
             user-agent : conda/22.9.0 requests/2.28.1 CPython/3.9.12 Linux/5.4.0-126-generic ubuntu/22.04.1 glibc/2.35
                UID:GID : 1000:1000
             netrc file : None
           offline mode : False
An unexpected error has occurred. Conda has prepared the above report.
The command '/bin/bash -c source ${CONDA_TARGET_DIR}/etc/profile.d/conda.sh && conda init bash' returned a non-zero code: 1

was introduced with the conda version jump from v4.12.0 to v22.9.0 (see also here) and that it is a bug, that is currently worked on.

So, this is a problem that needs to be fixed upstream. For now, we therefore simply drop the conda update conda part after the miniconda latest installation, thereby sticking to the older conda 4.14.0 package, that is still distributed via Miniconda3-latest-Linux-x86_64.sh.