🔨 Fix make open-report for Darwin

Makefile

@@ -3,6 +3,12 @@ OUT=my-log
 GOBIN=$(shell go env GOBIN)
 COVEROUT=cover.out
 COVERHTML=cover.html
+OPEN=xdg-open
+OS=$(shell uname -s)
+
+ifeq ($(OS),Darwin)
+OPEN=open
+endif
 
 .PHONY: help
 help: ## Show help for documented recipes
@@ -35,7 +41,7 @@ report: $(COVERHTML) ## Generate a coverage report
 
 .PHONY: open-report
 open-report: $(COVERHTML) ## Open the coverage report in the default browser
-	xdg-open $(COVERHTML)
+	$(OPEN) $<
 
 .PHONY: build
 build: $(OUT) ## Builds the application