[chore] update otel libraries (#3740)

* chore: update otel dependencies

* refactor: combine tracing & metrics in observability package

* chore: update example tracing compose file

vendor/google.golang.org/grpc/internal/idle/idle.go

@@ -182,6 +182,7 @@ func (m *Manager) tryEnterIdleMode() bool {
 	return true
 }
 
+// EnterIdleModeForTesting instructs the channel to enter idle mode.
 func (m *Manager) EnterIdleModeForTesting() {
 	m.tryEnterIdleMode()
 }
@@ -225,7 +226,7 @@ func (m *Manager) ExitIdleMode() error {
 		//   came in and OnCallBegin() noticed that the calls count is negative.
 		// - Channel is in idle mode, and multiple new RPCs come in at the same
 		//   time, all of them notice a negative calls count in OnCallBegin and get
-		//   here. The first one to get the lock would got the channel to exit idle.
+		//   here. The first one to get the lock would get the channel to exit idle.
 		// - Channel is not in idle mode, and the user calls Connect which calls
 		//   m.ExitIdleMode.
 		//
@@ -266,6 +267,7 @@ func (m *Manager) isClosed() bool {
 	return atomic.LoadInt32(&m.closed) == 1
 }
 
+// Close stops the timer associated with the Manager, if it exists.
 func (m *Manager) Close() {
 	atomic.StoreInt32(&m.closed, 1)