Use specified GO var to generate go.work (#26508)

Co-authored-by: Mattermost Build <build@mattermost.com>

server/Makefile

@@ -391,11 +391,11 @@ setup-go-work: ## Sets up your go.work file
 ifneq ($(IGNORE_GO_WORK_IF_EXISTS),true)
 	@echo "Creating a go.work file"
 	rm -f go.work
-	go work init
+	$(GO) work init
-	go work use .
+	$(GO) work use .
-	go work use ./public
+	$(GO) work use ./public
 ifeq ($(BUILD_ENTERPRISE_READY),true)
-	go work use ../../enterprise
+	$(GO) work use ../../enterprise
 endif
 endif