chore: add message for successful initialization

PR-URL: #1401
Closes: #1400

Adds a success message in the Makefile, which shows up on successful initialization of development environment.

Reviewed-by: Philipp Burckhardt <pburckhardt@outlook.com>

tools/make/lib/init/Makefile

@@ -36,5 +36,6 @@ include $(TOOLS_MAKE_LIB_DIR)/init/git_hooks.mk
 # make init
 #/
 init: init-git-hooks init-eslint-plugins
+	@echo "Initialization Successful."
 
 .PHONY: init