Update CHANGELOG.md (#5492)

Author: renkelvin

FirebaseAuth/CHANGELOG.md

@@ -1,13 +1,12 @@
-# v6.5.4
-- [fixed] Suppress deprecation warnings when targeting iOS versions up to iOS 13. (#5437)
-
 # v6.5.3
-- [fixed] Handle calls to `useUserAccessGroup` soon after configure. (#4175)
+- [changed] Remove unused mfa request field "mfa_provider" (#5397)
+- [fixed] Suppress deprecation warnings when targeting iOS versions up to iOS 13. (#5437)
 
 # v6.5.2
-- [changed] File structure changes. No functional change.
+- [fixed] Handle calls to `useUserAccessGroup` soon after configure. (#4175)
 
 # v6.5.1
+- [changed] File structure changes. No functional change.
 - [changed] Code formatting changes.
 
 # v6.5.0