[CherryPick v1.12] Fix delete dataupload datadownload CR failure

[qiuming-best]

Fix delete dataupload datadownload CR failure when Velero uninstall

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Please add a summary of your change

Does your change fix a particular issue?

Fixes #(issue)
#6687

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• 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.

[codecov]

Codecov Report

Merging #6701 (5480acf) into release-1.12 (e2d3e84) will not change coverage.
The diff coverage is 100.00%.

@@              Coverage Diff              @@
##           release-1.12    #6701   +/-   ##
=============================================
  Coverage         60.36%   60.36%           
=============================================
  Files               242      242           
  Lines             25979    25979           
=============================================
  Hits              15683    15683           
  Misses             9194     9194           
  Partials           1102     1102           

Files Changed	Coverage Δ
pkg/controller/data_download_controller.go	75.18% <100.00%> (ø)
pkg/controller/data_upload_controller.go	68.25% <100.00%> (ø)