enhance: field stringtype maxlength raise to 1M

[JsDove]

enhance: field stringtype maxlength raise to 1M
issue: #37436

[sre-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: JsDove
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[mergify]

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.

Project coverage is 81.01%. Comparing base (306e5e6) to head (bd91bf1).
Report is 3 commits behind head on master.

Files with missing lines	Patch %	Lines
internal/proxy/task.go	0.00%	1 Missing ⚠️
internal/proxy/util.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #38582      +/-   ##
==========================================
+ Coverage   80.99%   81.01%   +0.02%     
==========================================
  Files        1379     1379              
  Lines      194492   194495       +3     
==========================================
+ Hits       157523   157570      +47     
+ Misses      31403    31370      -33     
+ Partials     5566     5555      -11     

Components	Coverage Δ
Client	75.88% <ø> (ø)
Core	69.33% <ø> (+0.01%)	⬆️
Go	83.05% <0.00%> (+0.02%)	⬆️

Files with missing lines	Coverage Δ
internal/proxy/task.go	80.69% <0.00%> (ø)
internal/proxy/util.go	89.63% <0.00%> (ø)

... and 32 files with indirect coverage changes

[mergify]

@JsDove Thanks for your contribution. Please submit with DCO, see the contributing guide https://github.com/milvus-io/milvus/blob/master/CONTRIBUTING.md#developer-certificate-of-origin-dco.

[mergify]

@JsDove go-sdk check failed, comment rerun go-sdk can trigger the job again.