Switch from GitLab to GitHub

[cameronrutherford]

Before Initial Switch:

• Clean up stale branches / issues (Consolidate remaining GitLab issues on GitHub and Cleanup branches #37)
• Merge any remaining work in MRs
• Issues moved from GitLab to GitHub (also move any stale PRs manually)
• PNNL GitLab push mirror (Add pipeline status configuration to PNNL #7)
• PNNL GPU pipelines posting status (Add pipeline status configuration to PNNL #7)
• Ascent pipelines posting status (Add pipeline status configuration to PNNL #7)

After Initial Switch:

• Tag new release to signify switch, and update spack package with URL + version (Planned 1.6.0)
  • Ensure tags are updated and all branches match
• Update about section and logo in GitHub (@abhyshr took care of this)
• Add Issue / Merge request template (Update Issue and Merge Request Template #36)
• Badges updated for pipelines / ExaGO logo update (Spack GitHub action #15)
  • This includes the new GitHub actions, and pre-commit (maybe codecov one day)
• Crusher pipelines fixed and posting status. (Add Crusher CI pipeline status #9)
• GitHub Actions pipelines
  • pre-commit instead of CMake based linting (Add GitHub actions for push mirror #5)
  • spack CI builds in GitHub actions for CPU only builds (CPU only build of ExaGO in GitHub actions #11 Spack GitHub action #15)

Follow up work:

• Quarto Documentation + GitHub wiki integration (Quarto Documentation Transition #32)
• Crusher CI status posting (Add Crusher CI pipeline status #9)
• Add spack module pipelines to Ascent and Crusher (Port Spack module rebuild pipelines to Ascent #10 Port Spack module rebuild pipelines to Crusher #34)
• Submodules removed in favor of external packages (Transition dependencies from submodules into spack #38)

[cameronrutherford]

pre-commit documentation is a must

[cameronrutherford]

In addition to MR / Issue template, we should include requirements to manually run and have crusher CI pass before merging. Can't enforce through GitHub, so this is a manual / optional req

[cameronrutherford]

Captured reamining tasks in sub issues