Multiple versions of Redis in grpd and gstg

In both gprd and gstg, it appears we are running two different versions of Redis according to /admin:

It looks like the redis-sidekiq nodes are running GitLab EE 13.2.5, while the other nodes are using 12.8.1:

 PRODUCTION secondary-redis stanhu@redis-sidekiq-01-db-gprd.c.gitlab-production.internal:~$ /opt/gitlab/embedded/bin/redis-server --version
Redis server v=5.0.9 sha=ce878b6e:0 malloc=jemalloc-5.1.0 bits=64 build=2bbe3a84de4963ad
 PRODUCTION secondary-redis stanhu@redis-sidekiq-01-db-gprd.c.gitlab-production.internal:~$ dpkg -l | grep gitlab-ee
ii  gitlab-ee                        13.2.5-ee.0                                amd64        GitLab Enterprise Edition (including NGINX, Postgres, Redis)

 PRODUCTION secondary-redis stanhu@redis-01-db-gprd.c.gitlab-production.internal:~$ /opt/gitlab/embedded/bin/redis-server --version
Redis server v=5.0.7 sha=4891612b:0 malloc=jemalloc-5.1.0 bits=64 build=d6045103b2547a75
 PRODUCTION secondary-redis stanhu@redis-01-db-gprd.c.gitlab-production.internal:~$ dpkg -l | grep gitlab
ii  gitlab-ee                         12.8.1-ee.0                                amd64        GitLab Enterprise Edition (including NGINX, Postgres, Redis)