fix: nil pointer dereference when failed to scan out the quota records from redis

[microyahoo]

Signed-off-by: Liang Zheng [email protected]

Comprehensive Summary of your change

Issue being fixed

Fixes 21045

Please indicate you've done the following:

• Well Written Title and Summary of the PR
• Label the PR as needed. "release-note/ignore-for-release, release-note/new-feature, release-note/update, release-note/enhancement, release-note/community, release-note/breaking-change, release-note/docs, release-note/infra, release-note/deprecation"
• Accepted the DCO. Commits without the DCO will delay acceptance.
• Made sure tests are passing and test coverage is added if needed.
• Considered the docs impact and opened a new docs issue or PR with docs changes if needed in website repository.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 66.08%. Comparing base (c8c11b4) to head (47c0278).
Report is 296 commits behind head on main.

Files with missing lines	Patch %	Lines
src/controller/quota/controller.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main   #21046       +/-   ##
===========================================
+ Coverage   45.36%   66.08%   +20.71%     
===========================================
  Files         244     1049      +805     
  Lines       13333   114603   +101270     
  Branches     2719     2856      +137     
===========================================
+ Hits         6049    75733    +69684     
- Misses       6983    34727    +27744     
- Partials      301     4143     +3842     

Flag	Coverage Δ
unittests	66.08% <0.00%> (+20.71%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
src/controller/quota/controller.go	31.66% <0.00%> (ø)

... and 1287 files with indirect coverage changes

[chlins]

lgtm

[wy65701436]

lgtm

[chlins]

lgtm