docs: remove duplicate words in three files (#12852)

src/documents/templating/filters.py

@@ -14,7 +14,7 @@ def localize_date(value: date | datetime | str, format: str, locale: str) -> str
     Args:
         value (date | datetime | str): The date or datetime to format. If a datetime
             is provided, it should be timezone-aware (e.g., UTC from a Django DB object).
-            if str is provided is is parsed as date.
+            If str is provided it is parsed as date.
         format (str): The format to use. Can be one of Babel's preset formats
             ('short', 'medium', 'long', 'full') or a custom pattern string.
         locale (str): The locale code (e.g., 'en_US', 'fr_FR') to use for

src/documents/tests/test_management_importer.py

@@ -313,7 +313,7 @@ class TestCommandImport(
         WHEN:
             - An import is attempted
         THEN:
-            - Warning about the the version mismatch is output
+            - Warning about the version mismatch is output
         """
         stdout = StringIO()