fix cov + clean testcache

.github/workflows/ccip-ocr3-build-lint-test.yml

@@ -46,7 +46,8 @@ jobs:
         run: |
           git fetch origin ${{ github.base_ref }}
           git checkout ${{ github.base_ref }}
-          { time TEST_COUNT=1 COVERAGE_FILE=coverage.out make test; } 2> test-results.txt
+          go clean -testcache
+          { time TEST_COUNT=1 COVERAGE_FILE=coverage_target.out make test; } 2> test-results.txt
           real_time=$(cat test-results.txt | grep real | awk '{print $2}')
           echo "tests_duration_target=$real_time" >> $GITHUB_ENV
           total=$(go tool cover -func=coverage_target.out | grep total | awk '{print $3}')