K8OP-295 Expose Medusa's gRPC server port configuration

[rzvoncek]

What this PR does:
This PR allows users of k8ssandra-operator to specify newly-added config field in Medusa that controls which port Medusa will use to start its gRPC server on.

Update: Manual testing discolosed some formatting issues (bad space type) in the to-be medusa config map. That's fixed now and the PR is ready to go.

Which issue(s) this PR fixes:
Fixes #1455

Checklist

• Changes manually tested
• Automated Tests added/updated
• Documentation added/updated
• CHANGELOG.md updated (not required for documentation PRs)
• CLA Signed: DataStax CLA

[rzvoncek]

@adejanovski , I've used the Github UI to resolve the merge conflict (it was just a changelog entry). But it now made a merge commit. I'm not sure that's what we want. Please let me know if it's a no-no and I'll redo this, most likely with an entirely new branch into which I'll cherry-pick the relevant commits.

[codecov]

Codecov Report

Attention: Patch coverage is 43.28358% with 38 lines in your changes missing coverage. Please review.

Project coverage is 58.99%. Comparing base (42de723) to head (176d33c).
Report is 26 commits behind head on main.

❗ Current head 176d33c differs from pull request most recent head c571de9

Please upload reports for the commit c571de9 to get more accurate results.

Files with missing lines	Patch %	Lines
pkg/cassandra/datacenter.go	0.00%	17 Missing ⚠️
controllers/medusa/medusatask_controller.go	33.33%	10 Missing and 2 partials ⚠️
controllers/medusa/medusabackupjob_controller.go	50.00%	4 Missing and 2 partials ⚠️
controllers/medusa/medusarestorejob_controller.go	50.00%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1456      +/-   ##
==========================================
- Coverage   59.02%   58.99%   -0.03%     
==========================================
  Files         125      125              
  Lines       12695    12763      +68     
==========================================
+ Hits         7493     7530      +37     
- Misses       4524     4553      +29     
- Partials      678      680       +2     

Files with missing lines	Coverage Δ
pkg/medusa/reconcile.go	70.67% <100.00%> (+0.42%)	⬆️
controllers/medusa/medusarestorejob_controller.go	56.67% <50.00%> (-0.28%)	⬇️
controllers/medusa/medusabackupjob_controller.go	60.80% <50.00%> (+2.10%)	⬆️
controllers/medusa/medusatask_controller.go	48.22% <33.33%> (-0.53%)	⬇️
pkg/cassandra/datacenter.go	64.44% <0.00%> (-2.74%)	⬇️

... and 3 files with indirect coverage changes

[rzvoncek]

I had to rebase this to resolve another conflict. The merge commit went away, and the CI is green.

[adejanovski]

Just one blocking comment on using a multi arch image by default, and one quick refactoring suggestion.

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
1.8% Duplication on New Code

See analysis details on SonarQube Cloud