fix: run coverage threshold check only on Linux

Author: nikolay-e

.github/workflows/ci.yml

@@ -126,6 +126,7 @@ jobs:
             --cov-report=term-missing --cov-branch --junitxml=test-results.xml
 
       - name: Coverage report with threshold
+        if: runner.os == 'Linux'
         run: |
           coverage report --fail-under=80