feat: Add MySQL ent-based storage driver

Signed-off-by: m.nabokikh <maksim.nabokikh@flant.com>

storage/ent/utils.go

@@ -0,0 +1,10 @@
+package ent
+
+import "os"
+
+func getenv(key, defaultVal string) string {
+	if val := os.Getenv(key); val != "" {
+		return val
+	}
+	return defaultVal
+}