feat: add last_scanned_row_responses to FeatureFlags (#845)

* feat: add last_scanned_row_key feature

PiperOrigin-RevId: 551191182

Source-Link: googleapis/googleapis@51e04ba

Source-Link: googleapis/googleapis-gen@4b90e8e
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google/cloud/bigtable_v2/types/feature_flags.py

@@ -48,6 +48,10 @@ class FeatureFlags(proto.Message):
             Notify the server that the client enables
             batch write flow control by requesting
             RateLimitInfo from MutateRowsResponse.
+        last_scanned_row_responses (bool):
+            Notify the server that the client supports the
+            last_scanned_row field in ReadRowsResponse for long-running
+            sparse scans.
     """
 
     reverse_scans: bool = proto.Field(
@@ -58,6 +62,10 @@ class FeatureFlags(proto.Message):
         proto.BOOL,
         number=3,
     )
+    last_scanned_row_responses: bool = proto.Field(
+        proto.BOOL,
+        number=4,
+    )
 
 
 __all__ = tuple(sorted(__protobuf__.manifest))