docs:update info of spring cloud integrates with polaris-java.

[SkyeBeFreeman]

Please provide issue(s) of this PR:
Fixes #393

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[codecov-commenter]

Codecov Report

Merging #394 (0efd1a9) into main (41b5ee3) will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #394   +/-   ##
=======================================
  Coverage   21.24%   21.25%           
=======================================
  Files         162      162           
  Lines       23073    23073           
=======================================
+ Hits         4903     4905    +2     
+ Misses      17391    17389    -2     
  Partials      779      779           

Impacted Files	Coverage Δ
store/boltdb/instance.go	53.80% <0.00%> (+0.47%)	⬆️

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