Fix: Overriding user defined labels

[varshaprasad96]

This PR fixes an issue where helm's postrenderer
used to override the user defined object labels instead of merging them.

Issue:
Previously, if any manifest in the bundle had labels provided in them, they were overwritten when bundle deployment was created.

[ncdc]

Could you please add a test that fails without the fix, and passes with it?

[codecov]

Codecov Report

Merging #666 (7802031) into main (2411f47) will decrease coverage by 10.70%.
Report is 2 commits behind head on main.
The diff coverage is 100.00%.

❗ Current head 7802031 differs from pull request most recent head f173729. Consider uploading reports for the commit f173729 to get more accurate results

@@             Coverage Diff             @@
##             main     #666       +/-   ##
===========================================
- Coverage   31.94%   21.24%   -10.70%     
===========================================
  Files          10       12        +2     
  Lines         479      772      +293     
===========================================
+ Hits          153      164       +11     
- Misses        304      583      +279     
- Partials       22       25        +3     

Files Changed	Coverage Δ
...l/controllers/bundledeployment/bundledeployment.go	3.76% <100.00%> (ø)

... and 1 file with indirect coverage changes

[varshaprasad96]

Could you please add a test that fails without the fix, and passes with it?

Done. This package did not have tests for bundleDeployment controller, I've added one just to cover this case for now.
Will create issue to add more add coverage to the controller.

[varshaprasad96]

Looks like manifests-diff maybe failing because my branch name, as it has a slash, where its trying to copy rukpak.yaml and is not able to find the path. Will close this and re-open the PR with a different branch name :/