[stable/mysql] Test pod/configmap expose credentials for DB

[jrnt30]

Noticed a small issue/concern with the current stable MySQL chart as we were playing around with it that I would consider a bug (or at least a departure from norms).

Issue:

• Currently has a templates/test/ directory for some hook tests to validate the configuration of the database.
• A ConfigMap is used to write out the test command to execute via the test hook
• The ConfigMap's script that is rendered makes direct use of the secret for the DB.

Suggested Solution:
Rework the test pod so that the password is injected in the same fashion it is for the "real" deployment. This would ensure that folks with lower privileges (i.e. unable to read secrets or exec into the pods themselves) would have a much harder time discovering the password in the first place.

[stale]

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[stale]

This issue is being automatically closed due to inactivity.