test(json-schema): add test of transformer in json-schema

[Zardddddd60]

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What have you changed?

add test of transformer in json-schema

[codecov]

Codecov Report

Merging #2975 (196793e) into formily_next (9990b66) will increase coverage by 0.05%.
The diff coverage is n/a.

@@               Coverage Diff                @@
##           formily_next    #2975      +/-   ##
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+ Coverage         96.00%   96.06%   +0.05%     
================================================
  Files               148      149       +1     
  Lines              6387     6482      +95     
  Branches           1720     1748      +28     
================================================
+ Hits               6132     6227      +95     
  Misses              255      255              

Impacted Files	Coverage Δ
packages/json-schema/src/transformer.ts	100.00% <ø> (ø)

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