chore: drop go1.14 support

[ubogdan]

Describe the PR
drop go 1.14 support

Relation issue
None.

Additional context
None.

[codecov]

Codecov Report

Merging #193 (ebdb6a3) into master (872c67c) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##            master      #193   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            1         1           
  Lines           91        91           
=========================================
  Hits            91        91           

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