Ensure all time counters don't have expiry date

What does this MR do and why?

The total counter keys should not expire as that will cause us to lose data if the keys are not updated continuously.

We started expiring keys due to a bug described here: !152475 (closed)

This issue only happened on gitlab.com.

See #461381 (closed) for context.

MR acceptance checklist

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How to set up and validate locally

1. In the Redis CLI:
   1. Create a Redis key with the {event_counters} prefix e.g. `INCR "{event_counters}_test"``
   2. Set the expiry for the new key: EXPIRE "{event_counters}_test" 10000
2. Apply the mirations bundle exec rake db:migrate
3. Verify that the new key has a TTL of -1: TTL "{event_counters}_test"

You can get inspiration for other interesting cases from the spec.

Related to #461381 (closed)