feat: support third party orm to interact with go-zero (#1286)

* fixes #987

* chore: fix test failure

* chore: add comments

* feat: support third party orm to interact with go-zero

* chore: refactor

zrpc/resolver/target_test.go

@@ -0,0 +1,17 @@
+package resolver
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestBuildDirectTarget(t *testing.T) {
+	target := BuildDirectTarget([]string{"localhost:123", "localhost:456"})
+	assert.Equal(t, "direct:///localhost:123,localhost:456", target)
+}
+
+func TestBuildDiscovTarget(t *testing.T) {
+	target := BuildDiscovTarget([]string{"localhost:123", "localhost:456"}, "foo")
+	assert.Equal(t, "discov://localhost:123,localhost:456/foo", target)
+}