fix backup_controller when credentials to volume snapshot location sh…

[yanggangtony]

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Please add a summary of your change

for _, location := range providerLocations {
		err = volume.UpdateVolumeSnapshotLocationWithCredentialConfig(location, b.credentialFileStore)
		if err != nil {
			errors = append(errors, fmt.Sprintf("error adding credentials to volume snapshot location named %s: %v", location.Name, err))
			continue
		}
	}

when errors is not nil , should return it .

Does your change fix a particular issue?

Fixes #(issue)

Please indicate you've done the following:

• Accepted the DCO. Commits without the DCO will delay acceptance.
• Created a changelog file or added /kind changelog-not-required as a comment on this pull request.
• Updated the corresponding documentation in site/content/docs/main.

[yanggangtony]

/kind changelog-not-required

[codecov]

Codecov Report

Merging #6653 (46ef54e) into main (411bd54) will decrease coverage by 0.01%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main    #6653      +/-   ##
==========================================
- Coverage   60.31%   60.31%   -0.01%     
==========================================
  Files         242      242              
  Lines       25924    25927       +3     
==========================================
  Hits        15637    15637              
- Misses       9186     9188       +2     
- Partials     1101     1102       +1     

Files Changed	Coverage Δ
pkg/controller/backup_controller.go	60.96% <0.00%> (-0.29%)	⬇️

[yanggangtony]

Two maintainer has approved.
Is these need a another maintainer to be merged?

[blackpiglet]

If this is not an urgent issue, I prefer to wait for the v1.12 release cut and RC.1, then we can merge this one to the main branch.

[yanggangtony]

OK , not in hurry.