Map gRPC.Internal to 400 in client metrics interceptor

This is done to align with the behavior of the
[ExceptionHandlingInterceptor](https://github.com/cashapp/misk/blob/8cffeac185c4b16bee379acfd112670656588d36/misk/src/main/kotlin/misk/web/exceptions/ExceptionHandlingInterceptor.kt#L176-L188)
which is based on the official doc for gRPC-to-HTTP status mappings
https://grpc.github.io/grpc/core/md_doc_http-grpc-status-mapping.html.
This will resolve inconsistencies between the metrics and actual HTTP
response.

Note: This approach maintains the consistencies for services using Misk
but might introduce discrepancies in metrics when interacting with
external gRPC services (e.g Armeria where the original mapping was
taken).
GitOrigin-RevId: aa2b18b2cc90183bae37b42e5ca7605b21ca6b53

misk/src/main/kotlin/misk/client/ClientMetricsInterceptor.kt

@@ -102,9 +102,9 @@ class ClientMetricsInterceptor private constructor(
  GrpcStatus.OK.code -> HTTP_OK
  GrpcStatus.CANCELLED.code -> HTTP_CLIENT_CLOSED_REQUEST
  GrpcStatus.UNKNOWN.code,
- GrpcStatus.INTERNAL.code,
  GrpcStatus.DATA_LOSS.code -> HTTP_INTERNAL_SERVER_ERROR
 
+ GrpcStatus.INTERNAL.code, // This aligns with the mapping in ExceptionHandler and https://grpc.github.io/grpc/core/md_doc_http-grpc-status-mapping.html
  GrpcStatus.INVALID_ARGUMENT.code,
  GrpcStatus.FAILED_PRECONDITION.code,
  GrpcStatus.OUT_OF_RANGE.code -> HTTP_BAD_REQUEST

misk/src/test/kotlin/misk/client/ClientMetricsInterceptorTest.kt

@@ -161,13 +161,13 @@ internal class ClientMetricsInterceptorTest {
  assertThat(clientHttp2.ping(AppRequest(200)).execute().code()).isEqualTo(200)
 
  SoftAssertions.assertSoftly { softly ->
- softly.assertThat(requestDurationSummary.labels("pingerHttp2.ping", "500").get().count.toInt()).isEqualTo(1)
+ softly.assertThat(requestDurationSummary.labels("pingerHttp2.ping", "500").get().count.toInt()).isEqualTo(0)
  softly.assertThat(requestDurationSummary.labels("pingerHttp2.ping", "200").get().count.toInt()).isEqualTo(1)
- softly.assertThat(requestDurationSummary.labels("pingerHttp2.ping", "400").get().count.toInt()).isEqualTo(1)
+ softly.assertThat(requestDurationSummary.labels("pingerHttp2.ping", "400").get().count.toInt()).isEqualTo(2)
 
- softly.assertThat(requestDurationHistogram.labels("pingerHttp2.ping", "500").get().buckets.last().toInt()).isEqualTo(1)
+ softly.assertThat(requestDurationHistogram.labels("pingerHttp2.ping", "500").get().buckets.last().toInt()).isEqualTo(0)
  softly.assertThat(requestDurationHistogram.labels("pingerHttp2.ping", "200").get().buckets.last().toInt()).isEqualTo(1)
- softly.assertThat(requestDurationHistogram.labels("pingerHttp2.ping", "400").get().buckets.last().toInt()).isEqualTo(1)
+ softly.assertThat(requestDurationHistogram.labels("pingerHttp2.ping", "400").get().buckets.last().toInt()).isEqualTo(2)
  }
  }