docs: [google-cloud-dataplex] Fix the comment for ignore_null field to clarify its applicability on data quality rules (googleapis#12141)

- [ ] Regenerate this pull request now.

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docs:Added documentation of page_size default and maximum value for
ListEntries and RetrieveAspects
PiperOrigin-RevId: 594334510

Source-Link:
googleapis/googleapis@75c4411

Source-Link:
https://github.com/googleapis/googleapis-gen/commit/25510307b3dd79c0077877872cc19fc5e697b5aa
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packages/google-cloud-dataplex/google/cloud/dataplex_v1/types/data_quality.py

@@ -437,7 +437,12 @@ class DataQualityRule(proto.Message):
             a rule, unless ``ignore_null`` is ``true``. In that case,
             such ``null`` rows are trivially considered passing.
 
-            This field is only valid for row-level type rules.
+            This field is only valid for the following type of rules:
+
+            -  RangeExpectation
+            -  RegexExpectation
+            -  SetExpectation
+            -  UniquenessExpectation
         dimension (str):
             Required. The dimension a rule belongs to. Results are also
             aggregated at the dimension level. Supported dimensions are