Fix leaking goroutine in memorylimiter (#9100)

**Description:**
Fixing a bug - described here
#9099

**Link to tracking Issue:**
#9099

**Testing:**
No tests added.
Unit tests were run

**Documentation:**
None

.chloggen/fix-leaking-goroutine-in-memorylimiter.yaml

@@ -0,0 +1,25 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: bug_fix
+
+# The name of the component, or a single word describing the area of concern, (e.g. otlpreceiver)
+component: memorylimiterprocessor
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Fixed leaking goroutines from memorylimiterprocessor
+
+# One or more tracking issues or pull requests related to the change
+issues: [9099]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

processor/memorylimiterprocessor/memorylimiter.go

@@ -63,6 +63,8 @@ type memoryLimiter struct {
 
 	refCounterLock sync.Mutex
 	refCounter     int
+	waitGroup      sync.WaitGroup
+	closed         chan struct{}
 }
 
 // Minimum interval between forced GC when in soft limited mode. We don't want to
@@ -141,6 +143,8 @@ func (ml *memoryLimiter) shutdown(context.Context) error {
 		return errShutdownNotStarted
 	} else if ml.refCounter == 1 {
 		ml.ticker.Stop()
+		close(ml.closed)
+		ml.waitGroup.Wait()
 	}
 	ml.refCounter--
 	return nil
@@ -226,8 +230,17 @@ func (ml *memoryLimiter) startMonitoring() {
 
 	ml.refCounter++
 	if ml.refCounter == 1 {
+		ml.closed = make(chan struct{})
+		ml.waitGroup.Add(1)
 		go func() {
-			for range ml.ticker.C {
+			defer ml.waitGroup.Done()
+
+			for {
+				select {
+				case <-ml.ticker.C:
+				case <-ml.closed:
+					return
+				}
 				ml.checkMemLimits()
 			}
 		}()