Pin sphinx_autodoc_typehints, fix MagicMock issues
Pin sphinx_autodoc_typehints, fix MagicMock issues

Fixes sphinx build failure:
```
Traceback (most recent call last):
  File "/home/runner/work/AMICI/AMICI/doc-venv/lib/python3.8/site-packages/sphinx/events.py", line 101, in emit
    results.append(listener.handler(self.app, *args))
  File "/home/runner/work/AMICI/AMICI/doc-venv/lib/python3.8/site-packages/sphinx_autodoc_typehints/__init__.py", line 446, in process_docstring
    type_hints = get_all_type_hints(obj, name)
  File "/home/runner/work/AMICI/AMICI/doc-venv/lib/python3.8/site-packages/sphinx_autodoc_typehints/__init__.py", line 263, in get_all_type_hints
    result = _get_type_hint(name, obj)
  File "/home/runner/work/AMICI/AMICI/doc-venv/lib/python3.8/site-packages/sphinx_autodoc_typehints/__init__.py", line 291, in _get_type_hint
    _resolve_type_guarded_imports(obj)
  File "/home/runner/work/AMICI/AMICI/doc-venv/lib/python3.8/site-packages/sphinx_autodoc_typehints/__init__.py", line 284, in _resolve_type_guarded_imports
    module_code = inspect.getsource(module)
  File "/opt/hostedtoolcache/Python/3.8.12/x64/lib/python3.8/inspect.py", line 997, in getsource
    lines, lnum = getsourcelines(object)
  File "/opt/hostedtoolcache/Python/3.8.12/x64/lib/python3.8/inspect.py", line 979, in getsourcelines
    lines, lnum = findsource(object)
  File "/opt/hostedtoolcache/Python/3.8.12/x64/lib/python3.8/inspect.py", line 780, in findsource
    file = getsourcefile(object)
  File "/opt/hostedtoolcache/Python/3.8.12/x64/lib/python3.8/inspect.py", line 696, in getsourcefile
    filename = getfile(object)
  File "/opt/hostedtoolcache/Python/3.8.12/x64/lib/python3.8/inspect.py", line 676, in getfile
    raise TypeError('module, class, method, function, traceback, frame, or '
TypeError: module, class, method, function, traceback, frame, or code object was expected, got MagicMock
```

FFroehlich/AMICI,FFroehlich/AMICI,FFroehlich/AMICI,FFroehlich/AMICI