update to latest golangci-lint (v1.30.0)

[techknowlogick]

as title

[codecov-commenter]

Codecov Report

Merging #12597 into master will decrease coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #12597      +/-   ##
==========================================
- Coverage   43.42%   43.39%   -0.03%     
==========================================
  Files         645      645              
  Lines       71288    71288              
==========================================
- Hits        30957    30936      -21     
- Misses      35317    35336      +19     
- Partials     5014     5016       +2     

Impacted Files	Coverage Δ
modules/util/timer.go	42.85% <0.00%> (-42.86%)	⬇️
modules/git/utils.go	73.77% <0.00%> (-3.28%)	⬇️
models/unit.go	46.57% <0.00%> (-2.74%)	⬇️
services/pull/check.go	47.69% <0.00%> (-2.31%)	⬇️
modules/charset/charset.go	68.53% <0.00%> (-2.25%)	⬇️
services/gitdiff/gitdiff.go	74.54% <0.00%> (-1.81%)	⬇️
modules/queue/unique_queue_disk_channel.go	53.84% <0.00%> (-1.54%)	⬇️
models/error.go	34.81% <0.00%> (-0.52%)	⬇️
modules/git/repo.go	49.23% <0.00%> (-0.51%)	⬇️
models/issue_comment.go	53.75% <0.00%> (-0.16%)	⬇️
... and 3 more

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[silverwind]

Surprised there are no new failures. Should we maybe update configuration to enable new "rules"?