Dependencies need to be pinned in ``pyproject.toml``

As title says.

Dependencies need to be specifically pinned for ``tests`` and ``doc`` as you are testing the CICD with those optional dependencies.
Which means that all the **mandatory** dependencies as well as all the optional dependencies (the ones already in ``tests`` for instance) need to be specifically pinned in the optional dependencies.

For instance, it would look like:

```
dependencies = [
"ansys-api-cfx>=0.3.0",
"ansys-platform-instancemanagement>=1.0.0",
.........
]

[project.optional-dependencies]
tests = [
"ansys-api-cfx==x.y.z", # latest compatible version
"ansys-platform-instancemanagement== x.y.z", # latest compatible version
.........
"pytest==9.1.1",
"pytest-cov==7.1.0",
"pytest-mock==3.15.1",
"pytest-xdist==3.8.0",
]
```

Open pyproject.toml and review the mandatory dependencies plus the existing tests and doc optional-dependency lists. Pin every mandatory and optional dependency to a specific compatible version, then verify that the tests and documentation dependency groups contain the required pinned packages.

Written by the indexing model from the issue text.