Bump Alpine version to 3.12

[vania-pooh]

No description provided.

[codecov]

Codecov Report

Merging #971 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #971   +/-   ##
=======================================
  Coverage   77.47%   77.47%           
=======================================
  Files          12       12           
  Lines        1514     1514           
=======================================
  Hits         1173     1173           
  Misses        262      262           
  Partials       79       79           

Flag	Coverage Δ
#go	77.47% <ø> (ø)

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