message: Prevent warning on GCC from no return after exahustive case.
  Handle spdlog::level::off by returning WasmResult::Ok;
diff: @@ -1161,8 +1161,9 @@ WasmResult Context::log(uint64_t level, absl::string_view message) {
  ENVOY_LOG(critical, "wasm log{}: {}", log_prefix(), message);
  return WasmResult::Ok;
  case spdlog::level::off:
  - NOT_IMPLEMENTED_GCOVR_EXCL_LINE;
  + return WasmResult::Ok;
  }
  + NOT_IMPLEMENTED_GCOVR_EXCL_LINE;
  }
  //
  @@ -1322,6 +1323,7 @@ Network::FilterStatus convertNetworkFilterStatus(proxy_wasm::FilterStatus status
  case proxy_wasm::FilterStatus::StopIteration:
  return Network::FilterStatus::StopIteration;
  }
  + NOT_IMPLEMENTED_GCOVR_EXCL_LINE;
  };
  Http::FilterHeadersStatus convertFilterHeadersStatus(proxy_wasm::FilterHeadersStatus status) {
  @@ -1331,6 +1333,7 @@ Http::FilterHeadersStatus convertFilterHeadersStatus(proxy_wasm::FilterHeadersSt
  case proxy_wasm::FilterHeadersStatus::StopIteration:
  return Http::FilterHeadersStatus::StopIteration;
  }
  + NOT_IMPLEMENTED_GCOVR_EXCL_LINE;
  };
  Http::FilterTrailersStatus convertFilterTrailersStatus(proxy_wasm::FilterTrailersStatus status) {
  @@ -1340,6 +1343,7 @@ Http::FilterTrailersStatus convertFilterTrailersStatus(proxy_wasm::FilterTrailer
  case proxy_wasm::FilterTrailersStatus::StopIteration:
  return Http::FilterTrailersStatus::StopIteration;
  }
  + NOT_IMPLEMENTED_GCOVR_EXCL_LINE;
  };
  Http::FilterMetadataStatus convertFilterMetadataStatus(proxy_wasm::FilterMetadataStatus status) {
  @@ -1347,6 +1351,7 @@ Http::FilterMetadataStatus convertFilterMetadataStatus(proxy_wasm::FilterMetadat
  case proxy_wasm::FilterMetadataStatus::Continue:
  return Http::FilterMetadataStatus::Continue;
  }
  + NOT_IMPLEMENTED_GCOVR_EXCL_LINE;
  };
  Http::FilterDataStatus convertFilterDataStatus(proxy_wasm::FilterDataStatus status) {
  @@ -1360,6 +1365,7 @@ Http::FilterDataStatus convertFilterDataStatus(proxy_wasm::FilterDataStatus stat
  case proxy_wasm::FilterDataStatus::StopIterationNoBuffer:
  return Http::FilterDataStatus::StopIterationNoBuffer;
  }
  + NOT_IMPLEMENTED_GCOVR_EXCL_LINE;
  };
  Network::FilterStatus Context::onNewConnection() {
  