Rename desc to description in PerfInfo

Bug: 201326605
Test: Ran go unit tests and verified the generated soong_metrics file.
Change-Id: I3ff0aa11e39f0a9862638706ae50550c78030cca
diff --git a/ui/metrics/event.go b/ui/metrics/event.go
index c3367e3..ebe664f 100644
--- a/ui/metrics/event.go
+++ b/ui/metrics/event.go
@@ -69,7 +69,7 @@
 func (e event) perfInfo() soong_metrics_proto.PerfInfo {
 	realTime := uint64(_now().Sub(e.start).Nanoseconds())
 	return soong_metrics_proto.PerfInfo{
-		Desc:                  proto.String(e.desc),
+		Description:           proto.String(e.desc),
 		Name:                  proto.String(e.name),
 		StartTime:             proto.Uint64(uint64(e.start.UnixNano())),
 		RealTime:              proto.Uint64(realTime),