feat: convert BackendTLSPolicies into service annotations

[mlavacca]

What this PR does / why we need it:

Which issue this PR fixes:

Part of #6631

Special notes for your reviewer:

PR Readiness Checklist:

Complete these before marking the PR as ready to review:

• the CHANGELOG.md release notes have been updated to reflect any significant (and particularly user-facing) changes introduced by this PR

[codecov]

Codecov Report

Attention: Patch coverage is 27.86885% with 44 lines in your changes missing coverage. Please review.

Project coverage is 53.9%. Comparing base (6533c42) to head (9d8d427).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
internal/dataplane/translator/ingressrules.go	31.4%	24 Missing ⚠️
internal/annotations/annotations.go	0.0%	11 Missing ⚠️
internal/store/store.go	40.0%	9 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff            @@
##            main   #6753      +/-   ##
========================================
- Coverage   77.7%   53.9%   -23.9%     
========================================
  Files        206     205       -1     
  Lines      24302   24370      +68     
========================================
- Hits       18894   13145    -5749     
- Misses      4440   10137    +5697     
- Partials     968    1088     +120     

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