disable test cache the idiomatic way

Makefile

@@ -1,22 +1,22 @@
-# GOFLAGS="-count=1" disables the test cache so that all tests are run every time.
+# go test -count=1 disables the test cache so that all tests are run every time.
 
 all: test integration examples
 
 test:
-	GOFLAGS="-count=1" go test -race ./...
+	go test -count=1 -race ./...
 
 lint:
 	staticcheck ./...
 
 integration:
-	GOFLAGS="-count=1" go test -race -v -tags=integration ./uatest/...
+	go test -count=1 -race -v -tags=integration ./uatest/...
 
 examples:
 	go build -o build/ ./examples/...
 
 test-race:
-	GOFLAGS="-count=1" go test -race ./...
-	GOFLAGS="-count=1" go test -race -v -tags=integration ./uatest/...
+	go test -count=1 -race ./...
+	go test -count=1 -race -v -tags=integration ./uatest/...
 
 install-py-opcua:
 	pip3 install opcua