Merge pull request #30583 from colemickens/fix-hack-path-handling

Automatic merge from submit-queue

fix path handling in hack/lib/init.sh

Jenkinsfile pipeline jobs get cloned into "\<project\> (\<branch\>)". As a result, I can't use certain things in `hack/lib/init.sh`.

This is a small fix for that problem.

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cluster/images/hyperkube/Makefile

@@ -110,6 +110,7 @@ else
 endif
 
 	docker build -t ${REGISTRY}/hyperkube-${ARCH}:${VERSION} ${TEMP_DIR}
+	rm -rf "${TEMP_DIR}"
 
 push: build
 	gcloud docker push ${REGISTRY}/hyperkube-${ARCH}:${VERSION}