SpiderMultusConfig: Fix error json tag for min/maxTxRateMbps (#4716)

[cyclinder]

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Notice:

• unite test or E2E test
• do not forget essential code comment and log
• document for the PR
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What issue(s) does this PR fix:

Fixes #4720

Special notes for your reviewer:

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 75.24%. Comparing base (4302a80) to head (ecd4d39).
Report is 1 commits behind head on release-v1.0.

Additional details and impacted files

@@               Coverage Diff                @@
##           release-v1.0    #4739      +/-   ##
================================================
+ Coverage         75.19%   75.24%   +0.04%     
================================================
  Files                56       56              
  Lines              6778     6778              
================================================
+ Hits               5097     5100       +3     
+ Misses             1468     1466       -2     
+ Partials            213      212       -1     

Flag	Coverage Δ
unittests	75.24% <ø> (+0.04%)	⬆️

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see 1 file with indirect coverage changes

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