🌱 Enable golangci-lint test presets

[spencerschrock]

What kind of change does this PR introduce?

linter

• PR title follows the guidelines defined in our pull request documentation

What is the current behavior?

• we explicitly disable all linters
• tparallel is disabled (because it's not explicitly enabled)

What is the new behavior (if this is a feature change)?**

• the disable-all flag is removed. There's only 6 linters enabled by default (currently) and we have them all enabled already (so no change here):
  • errcheck
  • gosimple
  • govet
  • ineffassign
  • staticcheck
  • unused
• the test preset is enabled, but 3/4 of the linters are disabled (1 which is hopefully temporary)
  • effectively only tparallel is enabled.

Overall this results in just 1 newly enabled linter: tparallel, which flags tests which use t.Parallel in the parent test, but not the children, or vice-versa. When fixing the errors, I favored parallelizing the tests when possible. For the dependencydiff tests, I chose to remove the t.Parallel calls due to the possibility of rate limiting mentioned in #2527

• [] Tests for the changes have been added (for bug fixes/features)

Which issue(s) this PR fixes

NONE

Special notes for your reviewer

This approach of enabling the presets and disabling problematic linters is something osv-scanner does, and which I'd like to try. My goal is to auto-pickup new linters whenever we bump our golangci-lint version. That being said, if the reviewer wish to keep the disable-all config, I'll change this PR to only enable tparallel explicitly, not through the test preset.

Does this PR introduce a user-facing change?

For user-facing changes, please add a concise, human-readable release note to
the release-note

(In particular, describe what changes users might need to make in their
application as a result of this pull request.)

NONE

[codecov]

Codecov Report

Merging #3594 (4196d19) into main (b15b47a) will decrease coverage by 5.88%.
The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3594      +/-   ##
==========================================
- Coverage   76.09%   70.22%   -5.88%     
==========================================
  Files         199      199              
  Lines       13741    13741              
==========================================
- Hits        10456     9649     -807     
- Misses       2674     3532     +858     
+ Partials      611      560      -51