Resolve "Update documentation on virtual env. for Alpha"

• fixed example for pytorch/torchvision in venv
• add workspace creation for venv in example
• add hint for workspaces and venv in general
• quick fix for deprecated JH section

Closes #533 (closed)

doc.zih.tu-dresden.de/docs/jobs_and_resources/alpha_centauri.md

@@ -128,11 +128,22 @@ marie@login.alpha$ module spider <module_name>
 additional Python packages and create an isolated runtime environment. We recommend using
 `virtualenv` for this purpose.
 
+
+!!! hint
+
+    We recommend to use [workspaces](../data_lifecycle/workspaces.md) for your
+    virtual environments.
+
+    
 ??? example "Example: Creating virtual environment and installing `torchvision` package"
 
     ```console
     marie@login.alpha$ srun --nodes=1 --cpus-per-task=1 --gres=gpu:1 --time=01:00:00 --pty bash -l
-    marie@alpha$ mkdir python-environments                               # please use workspaces
+    marie@alpha$ ws_allocate python_virtual_environment 1
+    Info: creating workspace.
+    /beegfs/ws/1/marie-python_virtual_environment
+    remaining extensions  : 2
+    remaining time in days: 1
     marie@alpha$ module load release/23.04 GCCcore/11.3.0 GCC/11.3.0 OpenMPI/4.1.4 Python/3.10.4
     Module GCC/11.3.0, OpenMPI/4.1.4, Python/3.10.4 and 21 dependencies loaded.
     marie@alpha$ module load PyTorch/1.12.1-CUDA-11.7.0
@@ -141,13 +152,13 @@ additional Python packages and create an isolated runtime environment. We recomm
     /software/rome/r23.04/Python/3.10.4-GCCcore-11.3.0/bin/python
     marie@alpha$ pip list
     [...]
-    marie@alpha$ virtualenv --system-site-packages python-environments/my-torch-env
+    marie@alpha$ virtualenv --system-site-packages /beegfs/ws/1/marie-python_virtual_environment/my-torch-env
     created virtual environment CPython3.8.6.final.0-64 in 42960ms
-      creator CPython3Posix(dest=~/python-environments/my-torch-env, clear=False, global=True)
+      creator CPython3Posix(dest=/beegfs/.global1/ws/marie-python_virtual_environment/my-torch-env, clear=False, global=True)
       seeder FromAppData(download=False, pip=bundle, setuptools=bundle, wheel=bundle, via=copy, app_data_dir=~/.local/share/virtualenv)
         added seed packages: pip==21.1.3, setuptools==57.2.0, wheel==0.36.2
       activators BashActivator,CShellActivator,FishActivator,PowerShellActivator,PythonActivator,XonshActivator
-    marie@alpha$ source python-environments/my-torch-env/bin/activate
+    marie@alpha$ source /beegfs/ws/1/marie-python_virtual_environment/my-torch-env/bin/activate
     (my-torch-env) marie@alpha$ pip install torchvision==0.13.1
     [...]
     Installing collected packages: torchvision