add docker-compose for local testing

docker-compose.yaml

+version: '3.3'
+services:
+  mysql:
+    # image: percona/percona-xtradb-cluster:latest
+    image: mariadb:10.4
+    # image: mysql:5.7
+    # image: mysql:8.0
+    environment:
+      MYSQL_DATABASE: 'mysql'
+      MYSQL_USER: 'mysql'
+      MYSQL_PASSWORD: 'mysql'
+      MYSQL_ROOT_PASSWORD: 'root'
+    ports:
+      - '127.0.0.1:3306:3306'

storage/sql/config_test.go

@@ -246,7 +246,7 @@ func TestMySQL(t *testing.T) {
 		NetworkDB: NetworkDB{
 			Database:          getenv("DEX_MYSQL_DATABASE", "mysql"),
 			User:              getenv("DEX_MYSQL_USER", "mysql"),
-			Password:          getenv("DEX_MYSQL_PASSWORD", ""),
+			Password:          getenv("DEX_MYSQL_PASSWORD", "mysql"),
 			Host:              host,
 			ConnectionTimeout: 5,
 		},