Fix all typos found under the FirebasePerformance/Tests/Unit directory (#13363)

Author: MojtabaHs

FirebasePerformance/Tests/Unit/Configurations/FPRRemoteConfigFlagsTest.m

@@ -46,7 +46,7 @@ - (void)testObjectEquality {
 }
 
 - (void)testCacheResetAfterEverySuccessfulFetch {
-  // Initializate the remote config and config flags
+  // Initialize the remote config and config flags
   FPRFakeRemoteConfig *remoteConfig = [[FPRFakeRemoteConfig alloc] init];
   FPRRemoteConfigFlags *configFlags =
       [[FPRRemoteConfigFlags alloc] initWithRemoteConfig:(FIRRemoteConfig *)remoteConfig];

FirebasePerformance/Tests/Unit/FPRNetworkTraceTest.m

@@ -191,7 +191,7 @@ - (void)testInitWithVeryLongURL {
   FPRNetworkTrace *trace = [[FPRNetworkTrace alloc] initWithURLRequest:sampleURLRequest];
   XCTAssertNotNil(trace);
 
-  // Expected lenght of the URL should be the domainLength, number of times path was appended which
+  // Expected length of the URL should be the domainLength, number of times path was appended which
   // does not make the length go beyond the max limit.
   NSInteger expectedLength = domainString.length + (numberOfAppends - 1) * appendString.length;
   XCTAssertEqual(trace.trimmedURLString.length, expectedLength);

FirebasePerformance/Tests/Unit/FPRTraceBackgroundActivityTrackerTest.m

@@ -36,7 +36,7 @@ - (void)testForegroundTracking {
   XCTAssertEqual(tracker.traceBackgroundState, FPRTraceStateForegroundOnly);
 }
 
-/** Validates if the foreground & backgound state is captured correctly. */
+/** Validates if the foreground & background state is captured correctly. */
 - (void)testBackgroundTracking {
   FPRTraceBackgroundActivityTracker *tracker = [[FPRTraceBackgroundActivityTracker alloc] init];
   NSNotificationCenter *defaultCenter = [NSNotificationCenter defaultCenter];

FirebasePerformance/Tests/Unit/Instruments/FPRNSURLSessionInstrumentTest.m

@@ -161,7 +161,7 @@ - (void)testSubclassIsNotRegisteredMoreThanOnce {
   [instrument deregisterInstrumentors];
 }
 
-/** Tests sessionWithConfiguration: with the default configurtion returns a non-nil object. */
+/** Tests sessionWithConfiguration: with the default configuration returns a non-nil object. */
 - (void)testSessionWithDefaultSessionConfiguration {
   FPRNSURLSessionInstrument *instrument = [[FPRNSURLSessionInstrument alloc] init];
   [instrument registerInstrumentors];

FirebasePerformance/Tests/Unit/Timer/FIRTraceTest.m

@@ -237,7 +237,7 @@ - (void)testSetOrIncrementMetricWithoutStart {
   XCTAssertNil([trace.counters objectForKey:@"testing"]);
 }
 
-/** Validates that calling get on a metric returns 0 if it hasnt been reviously set. */
+/** Validates that calling get on a metric returns 0 if it hasn't been reviously set. */
 - (void)testGetMetricWhenSetHasntBeenCalledReturnsZero {
   FIRTrace *trace = [[FIRTrace alloc] initWithName:@"Random"];
   int64_t metricValue = [trace valueForIntMetric:@"testing"];