Bump golang.org/x/crypto to v0.31.0 to fix CVEs.

[blackpiglet]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 59.12%. Comparing base (f96b1c2) to head (a10d78c).
Report is 2 commits behind head on release-1.15.

Additional details and impacted files

@@              Coverage Diff              @@
##           release-1.15    #8519   +/-   ##
=============================================
  Coverage         59.12%   59.12%           
=============================================
  Files               367      367           
  Lines             39118    39118           
=============================================
  Hits              23130    23130           
  Misses            14520    14520           
  Partials           1468     1468           

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[kaovilai]

lgtm