fix: resolve outstanding golint errors

[piksel]

Fixes the various errors that show up when running golint ./... locally, effectively hiding any relevant problems in the noise.

[codecov]

Codecov Report

Merging #124 (cb3adaf) into main (c7b9fb9) will increase coverage by 0.01%.
The diff coverage is 50.00%.

@@            Coverage Diff             @@
##             main     #124      +/-   ##
==========================================
+ Coverage   58.54%   58.55%   +0.01%     
==========================================
  Files          55       55              
  Lines        1165     1163       -2     
==========================================
- Hits          682      681       -1     
+ Misses        434      433       -1     
  Partials       49       49              

Impacted Files	Coverage Δ
pkg/services/smtp/smtp.go	82.01% <0.00%> (+0.58%)	⬆️
pkg/services/smtp/smtp_encmethod.go	62.50% <ø> (ø)
pkg/services/standard/standard_failures.go	0.00% <ø> (ø)
pkg/services/rocketchat/rocketchat.go	14.28% <100.00%> (-3.90%)	⬇️

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