Fix wrong keyspace replication factor alteration when multiple dcs with the same name exist

[adejanovski]

What this PR does:
Uses a proper cluster label filter when listing pods.

Which issue(s) this PR fixes:
Fixes #1188

Checklist

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

[codecov]

Codecov Report

Attention: 2 lines in your changes are missing coverage. Please review.

Comparison is base (651e3f7) 57.13% compared to head (792789d) 57.30%.
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1189      +/-   ##
==========================================
+ Coverage   57.13%   57.30%   +0.16%     
==========================================
  Files         103      103              
  Lines       10618    10618              
==========================================
+ Hits         6067     6085      +18     
+ Misses       4023     4008      -15     
+ Partials      528      525       -3     

Files	Coverage Δ
pkg/cassandra/management.go	0.00% <0.00%> (ø)

... and 6 files with indirect coverage changes

[sonarcloud]

Quality Gate passed

Kudos, no new issues were introduced!

0 New issues
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud