Added linkcheck action to makefile

Author: anshuman-agarwala

Makefile

@@ -587,6 +587,11 @@ endif
 yamllint:
 	@docker run --rm $$(tty -s && echo "-it" || echo) -v $(PWD):/data cytopia/yamllint:latest /data --config-file /data/.yamllint --no-warnings
 
+MD_FILES := $(shell find . -iname "*.md")
+.PHONY: linkcheck
+linkcheck:
+	docker run --init -w /input -v $(PWD):/input --rm -it ghcr.io/tcort/markdown-link-check:3.12 -q -p $(MD_FILES)
+
 ## --------------------------------------
 ## Cleanup / Verification
 ## --------------------------------------