Enable feature flag exact_pagination_token_match by default

Contributes to https://gitlab.com/gitlab-org/gitaly/-/issues/3817

Changelog: changed

internal/metadata/featureflag/ff_exact_pagination_token_match.go

@@ -2,4 +2,4 @@ package featureflag
 
 // ExactPaginationTokenMatch enables exact matching for provided pagination tokens and
 // returns an error if the match is not found.
-var ExactPaginationTokenMatch = NewFeatureFlag("exact_pagination_token_match", false)
+var ExactPaginationTokenMatch = NewFeatureFlag("exact_pagination_token_match", true)