fix: Referencing empty objects during tcproute and httproute updates

[AlinsRan]

Type of change:

• Bugfix
• New feature provided
• Improve performance
• Backport patches
• Documentation
• Refactor
• Chore
• CI/CD or Tests

What this PR does / why we need it:

close: #1826

Pre-submission checklist:

• Did you explain what problem does this PR solve? Or what new features have been added?
• Have you added corresponding test cases?
• Have you modified the corresponding document?
• Is this PR backward compatible? If it is not backward compatible, please discuss on the mailing list first

[codecov-commenter]

Codecov Report

Merging #1825 (b236399) into master (98ff8e5) will increase coverage by 0.14%.
The diff coverage is 0.00%.

❗ Current head b236399 differs from pull request most recent head e2f68b3. Consider uploading reports for the commit e2f68b3 to get more accurate results

@@            Coverage Diff             @@
##           master    #1825      +/-   ##
==========================================
+ Coverage   39.30%   39.45%   +0.14%     
==========================================
  Files          91       91              
  Lines        8073     8043      -30     
==========================================
  Hits         3173     3173              
+ Misses       4494     4463      -31     
- Partials      406      407       +1     

Impacted Files	Coverage Δ
pkg/apisix/cluster.go	28.37% <0.00%> (+0.23%)	⬆️
...kg/providers/apisix/translation/apisix_consumer.go	65.21% <0.00%> (-1.95%)	⬇️
pkg/providers/ingress/ingress.go	4.98% <0.00%> (+0.44%)	⬆️
pkg/providers/ingress/translation/translator.go	0.00% <0.00%> (ø)

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