[Python] Redis cache support for enrichment transform (#30307)

* redis cache support for enrichment transform

* update rrio test

* convert rrio tests to execute pipeline, tagged outputs, cache_request_key

* fix rrio exception test, add to changes

* get_cache_key, doc comments, changed __all__

* fix pydoc

* use pool manager

* revert test

* use property() for setter

CHANGES.md

@@ -65,8 +65,8 @@
 
 ## New Features / Improvements
 
-* [Enrichment Transform](https://s.apache.org/enrichment-transform) along with GCP BigTable handler added to Python SDK ([#30001](https://github.com/apache/beam/pull/30001)).
 * Allow writing clustered and not time partitioned BigQuery tables (Java) ([#30094](https://github.com/apache/beam/pull/30094)).
+* Redis cache support added to RequestResponseIO and Enrichment transform (Python) ([#30307](https://github.com/apache/beam/pull/30307))
 * Merged sdks/java/fn-execution and runners/core-construction-java into the main SDK. These artifacts were never meant for users, but noting
   that they no longer exist. These are steps to bring portability into the core SDK alongside all other core functionality.