Tighten release tag filter in galexie workflow (#75)

The previous `galexie-v*` glob matched any string starting with the
prefix, including tags containing shell metacharacters that could be
re-evaluated when downstream tooling expands `RELEASE_VERSION` into a
shell command. Constrain the filter to well-formed semver tags
(`galexie-vX.Y.Z` and `galexie-vX.Y.Z-rcN`) so non-conforming tags
never trigger a release build.

Author: urvisavla

.github/workflows/galexie.yml

@@ -5,7 +5,9 @@ on:
     branches:
       - main
       - 'release/**'
-    tags: ['galexie-v*']
+    tags:
+      - 'galexie-v[0-9]+.[0-9]+.[0-9]+'
+      - 'galexie-v[0-9]+.[0-9]+.[0-9]+-rc[0-9]+'
   pull_request:
 
 jobs: