Moved golangci linter config to the separate file

[begmaroman]

Description

Moved golangci config to the single file so github actions and local setup could use the same config file. Fixed existing linter issues.

Changes include

• Bugfix (non-breaking change that solves an issue)
• Hotfix (change that solves an urgent issue, and requires immediate attention)
• New feature (non-breaking change that adds functionality)
• Breaking change (change that is not backwards-compatible and/or changes current functionality)

Checklist

• I have assigned this PR to myself
• I have added at least 1 reviewer
• I have added the relevant labels
• I have updated the official documentation
• I have added sufficient documentation in code

Testing

• I have tested this code with the official test suite
• I have tested this code manually

[codecov]

Codecov Report

Merging #764 (9bea3f3) into develop (29177a3) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           develop     #764      +/-   ##
===========================================
+ Coverage    52.48%   52.50%   +0.01%     
===========================================
  Files          130      130              
  Lines        17069    17063       -6     
===========================================
  Hits          8959     8959              
+ Misses        7466     7460       -6     
  Partials       644      644              

Impacted Files	Coverage Δ
helper/keccak/keccak.go	0.00% <ø> (ø)
helper/keccak/pool.go	0.00% <ø> (ø)
jsonrpc/eth_endpoint.go	71.49% <ø> (ø)
types/receipt.go	11.82% <ø> (+0.24%)	⬆️
state/txn.go	19.76% <100.00%> (ø)
types/buildroot/buildroot_fast.go	79.16% <100.00%> (ø)

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[vcastellm]

This will play nicely with our local IDE, nice one!

[zivkovicmilos]

Looks good 💯

I've left a couple of comments on the config file itself

[0xAleksaOpacic]

LGTM