ci: skip coverage tasks for test infrastructure (#6934)

.github/workflows/coverage.yml

@@ -76,6 +76,7 @@ jobs:
         with:
           PATTERNS: |
             **/**.go
+            "!test/"
             go.mod
             go.sum
       - uses: actions/download-artifact@v2
@@ -104,6 +105,7 @@ jobs:
         with:
           PATTERNS: |
             **/**.go
+            "!test/"
             go.mod
             go.sum
       - uses: actions/download-artifact@v2