Use correct platform identifier for Apple Silicon / M1 docker images

[cedricziel]

Use correct arm64 platform for building docker images.

My previous PR in #960 used the wrong platform for M1/Apple silicon

[codecov]

Codecov Report

Merging #961 (af826a3) into main (72e9f56) will not change coverage.
The diff coverage is n/a.

❗ Current head af826a3 differs from pull request most recent head f62f28a. Consider uploading reports for the commit f62f28a to get more accurate results

Additional details and impacted files

@@            Coverage Diff            @@
##               main     #961   +/-   ##
=========================================
  Coverage     83.34%   83.34%           
  Complexity     2126     2126           
=========================================
  Files           277      277           
  Lines          6105     6105           
=========================================
  Hits           5088     5088           
  Misses         1017     1017           

Flag	Coverage Δ
7.4	81.98% <ø> (ø)
8.0	83.29% <ø> (ø)
8.1	83.42% <ø> (ø)
8.2	83.42% <ø> (ø)

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