CI/pathogen-repo-ci-v0: fix avian-flu build-args

[joverlee521]

Description of proposed changes

Follow up on nextstrain/avian-flu#103

Related issue(s)

Part of nextstrain/public#20

Checklist

• Automated checks pass
• Check if you need to add a changelog message
• Check if you need to add tests
• Check if you need to update docs

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 73.21%. Comparing base (7a0dfc8) to head (f724f55).
Report is 2 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1771   +/-   ##
=======================================
  Coverage   73.21%   73.21%           
=======================================
  Files          79       79           
  Lines        8395     8395           
  Branches     1713     1713           
=======================================
  Hits         6146     6146           
  Misses       1960     1960           
  Partials      289      289           

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[joverlee521]

Merging without review since the avian-flu CI workflow completed successfully.