firestore: add BatchWrite to gapic yaml

PiperOrigin-RevId: 319105199

google/firestore/v1/firestore_gapic.yaml

@@ -32,6 +32,10 @@ interfaces:
     - UNAVAILABLE
     - INTERNAL
     - DEADLINE_EXCEEDED
+  - name: aborted_unavailable
+    retry_codes:
+    - ABORTED
+    - UNAVAILABLE
   retry_params_def:
   - name: default
     initial_retry_delay_millis: 100
@@ -64,6 +68,9 @@ interfaces:
   - name: BatchGetDocuments
     retry_codes_name: idempotent
     retry_params_name: streaming
+  - name: BatchWrite
+    retry_codes_name: aborted_unavailable
+    retry_params_name: default
   - name: BeginTransaction
     retry_codes_name: idempotent
     retry_params_name: default