refactor: use builtin min/max funcs

[wass3rw3rk]

see "Changes to the language" for Go 1.21 release notes or the spec

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 0% with 17 lines in your changes missing coverage. Please review.

Project coverage is 52.18%. Comparing base (8b07da9) to head (eb42802). Report is 1 commits behind head on main.

Files	Patch %	Lines
api/repo/update.go	0.00%	4 Missing :warning:
api/build/list_org.go	0.00%	1 Missing :warning:
api/build/list_repo.go	0.00%	1 Missing :warning:
api/deployment/list.go	0.00%	1 Missing :warning:
api/hook/list.go	0.00%	1 Missing :warning:
api/log/list_build.go	0.00%	1 Missing :warning:
api/pipeline/list.go	0.00%	1 Missing :warning:
api/repo/list.go	0.00%	1 Missing :warning:
api/repo/list_org.go	0.00%	1 Missing :warning:
api/schedule/list.go	0.00%	1 Missing :warning:
... and 4 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1148      +/-   ##
==========================================
+ Coverage   52.11%   52.18%   +0.07%     
==========================================
  Files         550      550              
  Lines       18859    18833      -26     
==========================================
  Hits         9828     9828              
+ Misses       8469     8443      -26     
  Partials      562      562              

Files	Coverage Δ
util/util.go	18.86% <ø> (+2.47%)	:arrow_up:
api/build/list_org.go	0.00% <0.00%> (ø)
api/build/list_repo.go	0.00% <0.00%> (ø)
api/deployment/list.go	0.00% <0.00%> (ø)
api/hook/list.go	0.00% <0.00%> (ø)
api/log/list_build.go	0.00% <0.00%> (ø)
api/pipeline/list.go	0.00% <0.00%> (ø)
api/repo/list.go	0.00% <0.00%> (ø)
api/repo/list_org.go	0.00% <0.00%> (ø)
api/schedule/list.go	0.00% <0.00%> (ø)
... and 5 more