Fix issue with uninitialized input parameter block data

[brryan]

PR Summary

Downstream we were finding input parameter hash mismatch errors when running with multiple MPI ranks on some problems. It turns out this was because we were using an input parameter block with no actual parameters belonging to that block. In this case, the max_len_parname and max_len_parvalue fields for the input block (which are checked during input parameter hashing) are uninitialized. This is a simple fix that solves the downstream issue.

PR Checklist

• Code passes cpplint
• New features are documented.
• Adds a test for any bugs fixed. Adds tests for new features.
• Code is formatted
• Changes are summarized in CHANGELOG.md
• Change is breaking (API, behavior, ...)
  • Change is additionally added to CHANGELOG.md in the breaking section
  • PR is marked as breaking
  • Short summary API changes at the top of the PR (plus optionally with an automated update/fix script)
• CI has been triggered on Darwin for performance regression tests.
• Docs build
• (@lanl.gov employees) Update copyright on changed files

[Yurlungur]

thanks for the catch!