GitHub actions run pr tests

[rerpha]

Description of work

Closes #416

This PR:

• removes jenkins job that runs inst_servers tests on PRs and periodically and replaces both with github actions
• adds a badge for the periodic runs so we see them regularly
• adds a requirements.txt for the above so that github actions can run the tests with a clean install
• uses pytest to collect tests rather than having lots of run_tests.py files which has caused issues with tests not being run in the past

next steps to do after this:

• sort server_common out - it uses some blockserver/dbserver imports (remove server_common dependencies on blockserver and dbserver #415)
• https://github.com/ISISComputingGroup/EPICS-inst_servers/compare/use_venvs?expand=1
• make server_common a separate repo/project that can be pip installed, add to this repo's requirements.txt
• do this PR but in reflectometryServer, make sure name is consistent (create_virtual_env.bat)
• run create_virtual_env.bat as a step in the upgrade scripts
• profit?

To test

see CI result.

Acceptance criteria

Jenkins is not used

After this is merged, please remove the jenkins job from the branch protection ruleset.

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Code Review

• Is the code of an acceptable quality?
• Has the author taken into account the multi-threaded nature of the code?
• Have the changes been recorded appropriately in a PR for release notes?
• Has the manual system tests spreadsheet been updated?

Functional Tests

• Do changes function as described? Add comments below that describe the tests performed.

Final steps

• Reviewer has updated the submodule in the main EPICS repo? See Reviewing work for the subModules of EPICS in the Git workflow page for details.
• Reviewer has merged the associated PR for the release notes

[rerpha]

needs ISISComputingGroup/reusable-workflows#15 to run pyright on windows for epicscorelibs...

[rerpha]

I cannot for the life of me figure out why pyright is whinging about not being able to find genie-python - it seems to use the same mechanism as the tests...

[rerpha]

think CI is broken because of pypa/distutils#336