Remove configs/templates_NOT_YET_CONVERTED_TO_SPACK_v1/* (on May 8)

[climbfuji]

Description

All in the title.

I will merge this PR on May 8, 2026.

If one of these templates is still needed, act now and update it for Spack v1, or you'll need to dig it out of the archives later.

Dependencies

None

Issues addressed

Closes #341

Applications affected

???

Systems affected

None

Testing

• CI: Note whether the automatic tests (GitHub actions tests that run automatically for every commit) pass or not
  • GitHub actions CI tests pass
  • GitHub actions CI tests do not pass (provide explanation)
  • GitHub actions CI tests skipped (provide explanation if necessary) none of the templates removed are used in CI
• New tests added: List and describe any new tests added to GitHub actions
  • ...
• Additional testing: Add information on any additional tests conducted
  • ...

Checklist

• This PR addresses one issue/problem/enhancement or has a very good reason for not doing so.
• These changes have been tested on the affected systems and applications.
• All dependency PRs/issues have been resolved and this PR can be merged.
• All necessary updates to the documentation (spack-stack wiki) will be made when this PR is merged none of the templates removed are documented in the Wiki~~