Make client robust to Rst from OkHTTP (#1358)

The
[OKHTTP](https://github.com/grpc/grpc-java/blob/d4fa0ecc07495097453b0a2848765f076b9e714c/okhttp/src/main/java/io/grpc/okhttp/OkHttpClientTransport.java#L1241)
transport uses slightly different error messages for RST Stream that
aren't caught by current screen scraping.  This adds a check for the
strict explicitly.

bug: Retry RST Stream on OKHTTP.

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google-cloud-bigquerystorage/src/main/java/com/google/cloud/bigquery/storage/util/Errors.java

@@ -74,6 +74,7 @@ public static boolean isRetryableInternalStatus(Status status) {
         && description != null
         && (description.contains("Received unexpected EOS ")
             || description.contains(" Rst ")
+            || description.contains("Rst Stream")
             || description.contains("RST_STREAM")
             || description.contains("Connection closed with unknown cause")
             || description.contains("HTTP/2 error code: INTERNAL_ERROR"));

google-cloud-bigquerystorage/src/test/java/com/google/cloud/bigquery/storage/util/ErrorsTest.java

@@ -42,6 +42,7 @@ public void testRetryableInternalForRstErrors() {
         Errors.isRetryableInternalStatus(
             Status.INTERNAL.withDescription(
                 "RST_STREAM closed stream. HTTP/2 error code: INTERNAL_ERROR")));
+    assertTrue(Errors.isRetryableInternalStatus(Status.INTERNAL.withDescription("Rst Stream")));
   }
 
   @Test