Redis::Namespace#exists? doesn't work

[alpaca-tc]

Ruby version:2.7.1p83
Sidekiq / Pro / Enterprise version(s): sidekiq-pro 5.1.1

Please include your initializer and any error message with the full backtrace.

Are you using an old version?
Have you checked the changelogs to see if your issue has been fixed in a later version?

https://github.com/mperham/sidekiq/blob/master/Changes.md
https://github.com/mperham/sidekiq/blob/master/Pro-Changes.md
https://github.com/mperham/sidekiq/blob/master/Ent-Changes.md

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RuntimeError: Did not find our own heartbeat within 10 seconds, that's bad (Most recent call first)

File /usr/local/bundle/gems/sidekiq-pro-5.1.1/lib/sidekiq/pro/super_fetch.rb line 229 in wait_for_heartbeat
File /usr/local/bundle/gems/sidekiq-pro-5.1.1/lib/sidekiq/pro/super_fetch.rb line 59 in block in startup
File /usr/local/bundle/gems/sidekiq-6.1.0/lib/sidekiq/util.rb line 15 in watchdog
File /usr/local/bundle/gems/sidekiq-pro-5.1.1/lib/sidekiq/pro/super_fetch.rb line 54 in startup
File /usr/local/bundle/gems/sidekiq-pro-5.1.1/lib/sidekiq/pro/super_fetch.rb line 43 in block (2 levels) in setup

Redis::Namespace doesn't support #exists?

redis.exists? doesn't work if sidekiq used Redis::Namespace as redis client. see details

Sorry, I didn't know how to send a PR to sidekiq-pro 😢
Please replace exists? with exists :) or let me know how to send PR to sidekiq-pro.

lib/sidekiq/pro/super_fetch.rb:191
lib/sidekiq/pro/super_fetch.rb:224

[alpaca-tc]

Fixed this problem resque/redis-namespace#171