eospac: new default version 6.5.0 (#26723)
eospac: new default version 6.5.0 (#26723)

* [pkg][new version] Provide eospac@6.5.0 and mark it as default.

* Merge in changes found in #21629

* Mark all alpha/beta versions as deprecated.

- Addresses @sethrj's recommendation
- Also add a note indicated why these versions are marked this way.
LLNL/spack,LLNL/spack,LLNL/spack,LLNL/spack,LLNL/spack