fix: Replace bash-specific regex with POSIX-compliant shell syntax

- Replace [[ =~ ]] regex pattern with grep + sed for compatibility
- Remove bash-specific BASH_REMATCH array usage
- Use POSIX-compliant shell commands for package renaming
- Fix syntax error that was causing CI workflow to fail
- Clean up trailing spaces for yamllint compliance

Resolves shell syntax error in CI workflow package renaming logic.

.forgejo/workflows/ci.yml

@@ -167,13 +167,11 @@ jobs:
               echo "Renaming packages with build version..."
               for pkg in ../*.deb; do
                 pkg_name=$(basename "$pkg")
-                pkg_ext="${pkg_name##*.}"
-                pkg_base="${pkg_name%.*}"
 
-                # Extract current version and replace with build version
-                if [[ "$pkg_name" =~ ^apt-ostree_([^-]+)_([^.]+)\.deb$ ]]; then
-                  current_version="${BASH_REMATCH[1]}"
-                  arch="${BASH_REMATCH[2]}"
+                # Extract current version and replace with build version using sed
+                if echo "$pkg_name" | grep -q "^apt-ostree_.*_.*\.deb$"; then
+                  # Extract architecture (last part before .deb)
+                  arch=$(echo "$pkg_name" | sed 's/.*_\([^.]*\)\.deb$/\1/')
                   new_name="apt-ostree_${BUILD_VERSION}_${arch}.deb"
                   echo "Renaming: $pkg_name -> $new_name"
                   cp "$pkg" "$new_name"