chore: add execute permission for charts-build.sh (#6687)

Signed-off-by: lyb <yebin.li@pingcap.com>

Author: lybcodes

Makefile

@@ -262,4 +262,4 @@ help: ## Display this help.
 
 .PHONY: charts/build
 charts/build:
-	./hack/charts-build.sh
+	bash ./hack/charts-build.sh