Makfile changes - Adding multi arch build support for docker image

Makefile

@@ -21,7 +21,7 @@ help:
 	@echo "\tmake push          -- pushes the litmus-go multi-arch image"
 	@echo "\tmake build-amd64   -- builds the litmus-go binary & docker amd64 image"
 	@echo "\tmake push-amd64    -- pushes the litmus-go amd64 image"
-	@echo "\tpush-multiarch		-- pushes the litmus-go multiarch image"
+	@echo "\tpush-multiarch	-- pushes the litmus-go multiarch image"
 	@echo ""
 
 .PHONY: all