Add new tests to presubmit, fix errors

monitoring/go/buildbot_ingest/bycommit.go

Index: monitoring/go/buildbot_ingest/bycommit.go
diff --git a/monitoring/go/buildbot_ingest/bycommit.go b/monitoring/go/buildbot_ingest/bycommit.go
index b9db779449603051bfba25e07e6a6e90bbbaf721..3e21711798c02cdd75f834bbeb2579a83bba8725 100644
--- a/monitoring/go/buildbot_ingest/bycommit.go
+++ b/monitoring/go/buildbot_ingest/bycommit.go
@@ -141,7 +141,7 @@ func getLastProcessedBuildOnBranch(dbClient *influxdb.Client, builder, master, b
 	}
 	series := results[0]
 	if series.Name != SERIES_BUILDBOT_BYCOMMIT {
-		return -1, fmt.Errorf("Query returned the wrong series: %q; expected: %s got: %S", q, SERIES_BUILDBOT_BYCOMMIT, series.Name)
+		return -1, fmt.Errorf("Query returned the wrong series: %q; expected: %s got: %s", q, SERIES_BUILDBOT_BYCOMMIT, series.Name)
 	}
 	if len(series.Columns) != 2 {
 		return -1, fmt.Errorf("Query returned incorrect number of columns: %q, %v", q, series.Columns)