Fix make manifests not building every time

Make target `manifests` has a dependency on build.sh which if untouched
wouldn't generate the manifests after the first run. This patch fixes it
by removing the `build.sh` dependency

Signed-off-by: Sunil Thaha <sthaha@redhat.com>

Makefile

@@ -28,7 +28,7 @@ generate: manifests **.md
 **.md: $(EMBEDMD_BIN) $(shell find examples) build.sh example.jsonnet
 	$(EMBEDMD_BIN) -w `find . -name "*.md" | grep -v vendor`
 
-manifests: examples/kustomize.jsonnet $(GOJSONTOYAML_BIN) vendor build.sh
+manifests: examples/kustomize.jsonnet $(GOJSONTOYAML_BIN) vendor
 	./build.sh $<
 
 vendor: $(JB_BIN) jsonnetfile.json jsonnetfile.lock.json