Update changelog

CHANGELOG.md

@@ -41,6 +41,7 @@
 * [ENHANCEMENT] Rename batches property of Trace to ResourceSpans to be OTEL compatible [#3895](https://github.com/grafana/tempo/pull/3895)
 * [ENHANCEMENT] Reduce memory consumption of query-frontend[#3888](https://github.com/grafana/tempo/pull/3888) (@joe-elliott)
 * [ENHANCEMENT] Reduce log level verbosity for e2e tests[#3900](https://github.com/grafana/tempo/pull/3900) (@javiermolinar)
+* [ENHANCEMENT] Implement polling tenants concurrently [#3647](https://github.com/grafana/tempo/pull/3647) (@zalegrala)
 * [BUGFIX] Fix panic in certain metrics queries using `rate()` with `by` [#3847](https://github.com/grafana/tempo/pull/3847) (@stoewer)
 * [BUGFIX] Fix double appending the primary iterator on second pass with event iterator [#3903](https://github.com/grafana/tempo/pull/3903) (@ie-pham)
 * [BUGFIX] Fix metrics queries when grouping by attributes that may not exist [#3734](https://github.com/grafana/tempo/pull/3734) (@mdisibio)