Fix minor bug in vendoring script changelog edits

Also apply vendoring.
closes #329

Author: sirosen

CHANGELOG.rst

@@ -9,7 +9,8 @@ Unreleased
 ----------
 
 .. vendor-insert-here
-- Update vendored schemas (2023-09-20)
+
+- Update vendored schemas (2023-09-27)
 - Add a ``--validator-class`` option for specifying a custom
   ``jsonschema.protocols.Validator`` class to use (:pr:`327`, :issue:`262`)
 - Minor fix to hook regexes to explicitly match `.` chars. Thanks

scripts/vendor-schemas.py

@@ -16,7 +16,8 @@
 VENDOR_SLUG = "\n.. vendor-insert-here\n"
 
 EXISTING_CHANGELINE_PATTERN = re.compile(
-    re.escape(f"{VENDOR_SLUG}\n- Update vendored schemas")
+    re.escape(VENDOR_SLUG)
+    + "\n?- Update vendored schemas"
     + r" \(\d{4}-\d{2}-\d{2}\)"
     + "\n",
     flags=re.MULTILINE,