Add module-level import re (fixes v1.12.4 NameError)

v1.12.4 moved the regex pre-compilation up to module scope but the
original vfb_queries.py only imported re lazily inside the old
encode_label function. Docker Image CI for v1.12.4 failed at module
import with `NameError: name 're' is not defined` on line 344.

One-line fix. py_compile clean. No behavioural change.

Author: Robbie1977

src/vfbquery/vfb_queries.py

@@ -12,6 +12,7 @@
 from urllib.parse import unquote
 from .solr_result_cache import with_solr_cache
 import time
+import re
 import requests
 import inspect