Merge branch 'add-redis-slow-log-demo-video' into 'master'

Add Redis slow log demo video

See merge request gitlab-org/gitlab!42710

doc/development/redis.md

@@ -96,10 +96,14 @@ requests that read the most data from the cache, we can just sort by
 
 ### The slow log
 
+TIP: **Tip:**
+There is a [video showing how to see the slow log](https://youtu.be/BBI68QuYRH8) (GitLab internal)
+on GitLab.com
+
 On GitLab.com, entries from the [Redis
 slow log](https://redis.io/commands/slowlog) are available in the
 `pubsub-redis-inf-gprd*` index with the [`redis.slowlog`
-tag](https://log.gprd.gitlab.net/app/kibana#/discover?_g=(filters:!(),refreshInterval:(pause:!t,value:0),time:(from:now-1d,to:now))&_a=(columns:!(json.type,json.command,json.exec_time),filters:!(('$state':(store:appState),meta:(alias:!n,disabled:!f,index:AWSQX_Vf93rHTYrsexmk,key:json.tag,negate:!f,params:(query:redis.slowlog),type:phrase),query:(match:(json.tag:(query:redis.slowlog,type:phrase))))),index:AWSQX_Vf93rHTYrsexmk)).
+tag](https://log.gprd.gitlab.net/app/kibana#/discover?_g=(filters:!(),refreshInterval:(pause:!t,value:0),time:(from:now-1d,to:now))&_a=(columns:!(json.type,json.command,json.exec_time_s),filters:!(('$state':(store:appState),meta:(alias:!n,disabled:!f,index:AWSQX_Vf93rHTYrsexmk,key:json.tag,negate:!f,params:(query:redis.slowlog),type:phrase),query:(match:(json.tag:(query:redis.slowlog,type:phrase))))),index:AWSQX_Vf93rHTYrsexmk)).
 This shows commands that have taken a long time and may be a performance
 concern.