Fix Ubuntu arm badge

[mcbarton]

Description

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This fixes the Ubuntu arm badge in the readme so it correctly displays Ubuntu arm.

Fixes # (issue)

Type of change

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• Bug fix
• New feature
• Requires documentation updates

Testing

Please describe the test(s) that you added and ran to verify your changes.

Checklist

• I have read the contribution guide recently

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 71.17%. Comparing base (d6b3bf7) to head (efc9895).
Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #482   +/-   ##
=======================================
  Coverage   71.17%   71.17%           
=======================================
  Files           9        9           
  Lines        3552     3552           
=======================================
  Hits         2528     2528           
  Misses       1024     1024