@W-23751548: Fix portable release asset discovery

[mlischetti]

Summary

• remove the unsupported grouped find name expression from the release publisher
• retain -type f so downloaded artifact directories with archive-like names are not uploaded

Root cause

The self-hosted release runner rejected the parenthesized find expression before it collected any assets:

find: invalid expression; expected to find a `)` but didn't see one

Verification

• Python YAML parsing for .github/workflows/release.yml
• shell fixture proving find -type f excludes a .zip directory while retaining four regular asset files
• git diff --check