[cherry-pick] fix: support customize cache db for business

[chlins]

Support to configure the customized redis db for cache layer and other misc business for core, by default the behavior is same with previous(stored in db 0).

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Comprehensive Summary of your change

Issue being fixed

Fixes #19169

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• Well Written Title and Summary of the PR
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• Made sure tests are passing and test coverage is added if needed.
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[codecov]

Codecov Report

Merging #19189 (fd12b0a) into release-2.7.0 (3db3d60) will decrease coverage by 0.04%.
The diff coverage is 0.00%.

@@                Coverage Diff                @@
##           release-2.7.0   #19189      +/-   ##
=================================================
- Coverage          66.42%   66.38%   -0.04%     
=================================================
  Files               1012     1012              
  Lines             108674   108692      +18     
  Branches            2678     2678              
=================================================
- Hits               72183    72153      -30     
- Misses             32526    32574      +48     
  Partials            3965     3965              

Flag	Coverage Δ
unittests	66.38% <0.00%> (-0.04%)	⬇️

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

Files Changed	Coverage Δ
src/lib/cache/cache.go	64.40% <0.00%> (-28.28%)	⬇️
src/pkg/cached/base_manager.go	40.00% <0.00%> (ø)

... and 6 files with indirect coverage changes

[wy65701436]

lgtm