fix(packages): fix specified user packages api path

[ysicing]

fix specified user packages api path

Error in getting specific user repository API path, should be /users/%v/packages, not /user/%v/packages

https://docs.github.com/en/rest/reference/packages#get-a-package-version-for-a-user

Signed-off-by: ysicing i@ysicing.me

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[ysicing]

@googlebot I signed it!

[codecov]

Codecov Report

Merging #2129 (b6ffeff) into master (72ec8bb) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #2129   +/-   ##
=======================================
  Coverage   97.78%   97.78%           
=======================================
  Files         112      112           
  Lines        9970     9970           
=======================================
  Hits         9749     9749           
  Misses        154      154           
  Partials       67       67           

Impacted Files	Coverage Δ
github/users_packages.go	100.00% <100.00%> (ø)

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[gmlewis]

Thank you, @ysicing !
LGTM.
Merging.