Enhance objc part of the FirebaseAuth tests (#13753)

Author: MojtabaHs

FirebaseAuth/Tests/SampleSwift/ObjCApiTests/FacebookAuthTests.m

@@ -39,7 +39,7 @@ @interface FacebookAuthTests : FIRAuthApiTestsBase
 @implementation FacebookAuthTests
 
 // TODO(#10752) - Update and fix the Facebook login Sample app and tests.
-- (void)SKIPtestSignInWithFaceboook {
+- (void)SKIPtestSignInWithFacebook {
   FIRAuth *auth = [FIRAuth auth];
   if (!auth) {
     XCTFail(@"Could not obtain auth object.");