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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[wy65701436]

lgtm

[codecov]

Codecov Report

Merging #19184 (7a933e2) into release-2.8.0 (3f10872) will decrease coverage by 0.07%.
The diff coverage is 0.00%.

@@                Coverage Diff                @@
##           release-2.8.0   #19184      +/-   ##
=================================================
- Coverage          67.40%   67.33%   -0.07%     
=================================================
  Files                984      984              
  Lines             107051   107069      +18     
  Branches            2671     2671              
=================================================
- Hits               72154    72093      -61     
- Misses             31020    31095      +75     
- Partials            3877     3881       +4     

Flag	Coverage Δ
unittests	67.33% <0.00%> (-0.07%)	⬇️

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 14 files with indirect coverage changes