CI: server-docker stage installs SDK from PyPI #680

The same issue as described in #662 applies to the server-docker stage of the pr.yml:

the job checks out the repository shallow, so setuptools_scm builds the local SDK as 0.1.dev1+g<sha>, which does not satisfy the basyx-python-sdk>=1.0.0 constraint of the server. Thus, pip install .[dev] replaces the local SDK with the PyPI release.

This makes develop fail as soon as the integration test code depends on an SDK change that is not released yet. The first time this happens in #660, for example on this action run.

The server-docker job should check out with fetch-depth: 0 as well, like the other jobs with a TODO(#592). The proper solution is tracked in #592.