feat: allow envFrom for specifying environment variables from configmap/secrets

[ericwyles]

Enhances the helm chart to support envFrom in addition to env. This allows users to have the archivista environment variables in an existing configmap or secret and let kubernetes load them to the deployment through envFrom.

What this PR does / why we need it

This allows use of secrets for configuring connections and also allows for operators that configure db user/pw at deploy time to be able to supply secrets containing the connection information.

Acceptance Criteria Met

• Docs changes if needed
• Testing changes if needed
• All workflow checks passing (automatically enforced)
• All review conversations resolved (automatically enforced)
• DCO Sign-off

Special notes for your reviewer:

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 1.62%. Comparing base (a035c62) to head (6dcbc06).
Report is 120 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #326       +/-   ##
==========================================
- Coverage   82.40%   1.62%   -80.78%     
==========================================
  Files          10     120      +110     
  Lines         358   28856    +28498     
==========================================
+ Hits          295     470      +175     
- Misses         43   28329    +28286     
- Partials       20      57       +37     

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