chore: update linting configuration

[mccutchen]

• Adopt revive as the local linter used by make lint
• Update to latest golangci-lint releases for CI

[codecov]

Codecov Report

Merging #154 (021383d) into main (844a11a) will not change coverage.
The diff coverage is 100.00%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #154   +/-   ##
=======================================
  Coverage   98.05%   98.05%           
=======================================
  Files           8        8           
  Lines        1591     1591           
=======================================
  Hits         1560     1560           
  Misses         22       22           
  Partials        9        9           

Files	Coverage Δ
httpbin/cmd/cmd.go	92.02% <ø> (ø)
httpbin/handlers.go	99.45% <100.00%> (ø)
httpbin/helpers.go	96.64% <100.00%> (ø)
httpbin/options.go	100.00% <ø> (ø)