build: docker multi-arch builds for x86 and arm

[iFergal]

This is a direct copy of @m00sey's keripy work in WebOfTrust/keripy#832 but for KERIA, hopefully no issues.

Adds arm docker builds and makes them available on the same tag for both architectures. (and resolves the re-publishing of old builds from --all-tags push)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.71%. Comparing base (18d3ad7) to head (287b6f5).
Report is 24 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #303      +/-   ##
==========================================
+ Coverage   93.06%   93.71%   +0.65%     
==========================================
  Files          36       36              
  Lines        7121     7941     +820     
==========================================
+ Hits         6627     7442     +815     
- Misses        494      499       +5     

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[2byrds]

'containerd' is funny. Since this is a direct copy from keripy, let's try it out