Makefile: Target bundle-build requires bundle

If one calls make bundle-build without a make bundle beforehand, it will
error out:

$ make bundle-build
docker build -f bundle.Dockerfile -t openshift-sandboxed-containers-operator-bundle:v1.3.2 .
unable to prepare context: unable to evaluate symlinks in Dockerfile path: lstat sandboxed-containers-operator/bundle.Dockerfile: no such file or directory

Signed-off-by: Eduardo Lima (Etrunko) <etrunko@redhat.com>

Makefile

@@ -189,7 +189,7 @@ bundle: manifests kustomize ## Generate bundle manifests and metadata, then vali
 	operator-sdk bundle validate ./bundle
 
 .PHONY: bundle-build
-bundle-build: ## Build the bundle image.
+bundle-build: bundle ## Build the bundle image.
 	docker build -f bundle.Dockerfile -t $(BUNDLE_IMG) .
 
 .PHONY: bundle-push