Use tr instead of bash syntax to do case conversion (FreeTubeApp#8620)

Author: absidue

.github/workflows/build.yml

@@ -86,9 +86,11 @@ jobs:
         original_version="$(jq -r '.version' package.json)"
         version="$original_version"
 
-        if [[ "${GITHUB_REF,,}" == *development* ]]; then
+        lower_case_ref="$(echo -E "$GITHUB_REF" | tr '[:upper:]' '[:lower:]')"
+
+        if [[ "$lower_case_ref" == *development* ]]; then
           version="${original_version}-nightly-${GITHUB_RUN_NUMBER}"
-        elif [[ "${GITHUB_REF^^}" == *RC* ]]; then
+        elif [[ "$lower_case_ref" == *rc* ]]; then
           version="${original_version}-RC-${GITHUB_RUN_NUMBER}"
         fi