Fix shellcheck failures in hack/verify-test-featuregates.sh

Author: k-toyoda-pi

hack/.shellcheck_failures

@@ -17,5 +17,4 @@
 ./cluster/validate-cluster.sh
 ./hack/lib/test.sh
 ./hack/test-integration.sh
-./hack/verify-test-featuregates.sh
 ./test/images/image-util.sh

hack/verify-test-featuregates.sh

@@ -26,7 +26,7 @@ cd "${KUBE_ROOT}"
 rc=0
 
 # find test files accessing the mutable global feature gate or interface
-direct_sets=$(grep -n --include '*_test.go' -R 'MutableFeatureGate' . 2>/dev/null) || true
+direct_sets=$(find -L . -name '*_test.go' -exec grep -Hn 'MutableFeatureGate' {} \; 2>/dev/null) || true
 if [[ -n "${direct_sets}" ]]; then
   echo "Test files may not access mutable global feature gates directly:" >&2
   echo "${direct_sets}" >&2
@@ -38,7 +38,7 @@ if [[ -n "${direct_sets}" ]]; then
 fi
 
 # find test files calling SetFeatureGateDuringTest and not calling the result
-missing_defers=$(grep -n --include '*_test.go' -R 'SetFeatureGateDuringTest' . 2>/dev/null | grep -E -v "defer .*\\)\\(\\)$") || true
+missing_defers=$(find -L . -name '*_test.go' -exec grep -Hn 'SetFeatureGateDuringTest' {} \; 2>/dev/null | grep -E -v "defer .*\\)\\(\\)$") || true
 if [[ -n "${missing_defers}" ]]; then
   echo "Invalid invocations of featuregatetesting.SetFeatureGateDuringTest():" >&2
   echo "${missing_defers}" >&2