Let tfdoc understand sensitive variables (#3925)

tools/tfdoc.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 
-# Copyright 2025 Google LLC
+# Copyright 2026 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -119,7 +119,7 @@ VAR_RE = re.compile(r'''(?smx)
     (?:^(.*?)$)
 ''')
 VAR_RE_TYPE = re.compile(r'([\(\{\}\)])')
-VAR_TEMPLATE = ('default', 'description', 'type', 'nullable')
+VAR_TEMPLATE = ('default', 'description', 'type', 'nullable', 'sensitive')
 
 Document = collections.namedtuple('Document',
                                   'content files variables outputs recipes',