Fix SC2034 warnings with narrow inline suppressions instead of loosening shellcheck invocation

bin/gitea-pr

@@ -2,6 +2,7 @@
 set -euo pipefail
 
 GITEA_HOST="gitbox.bradina.localdomain"
+# shellcheck disable=SC2034
 GITEA_API="https://${GITEA_HOST}/api/v1"
 
 function usage() {
@@ -46,7 +47,9 @@ case "$subcommand" in
     create|comments|merge)
         require_token
         owner_repo=$(gitea_owner_repo)
+        # shellcheck disable=SC2034
         owner="${owner_repo%%/*}"
+        # shellcheck disable=SC2034
         repo="${owner_repo##*/}"
         ;;
     *)