dialect/sql/schema: json column migration for mariadb10.3.13

See https://github.com/ent/ent/issues/1395\#issuecomment-809420881
Fixed #1395

.github/workflows/ci.yml

@@ -141,6 +141,19 @@ jobs:
           --health-start-period 10s
           --health-timeout 5s
           --health-retries 10
+      maria103:
+        image: mariadb:10.3.13
+        env:
+          MYSQL_DATABASE: test
+          MYSQL_ROOT_PASSWORD: pass
+        ports:
+          - 4308:3306
+        options: >-
+          --health-cmd "mysqladmin ping -ppass"
+          --health-interval 10s
+          --health-start-period 10s
+          --health-timeout 5s
+          --health-retries 10
       postgres10:
         image: postgres:10
         env:
@@ -280,6 +293,19 @@ jobs:
           --health-start-period 10s
           --health-timeout 5s
           --health-retries 10
+      maria103:
+        image: mariadb:10.3.13
+        env:
+          MYSQL_DATABASE: test
+          MYSQL_ROOT_PASSWORD: pass
+        ports:
+          - 4308:3306
+        options: >-
+          --health-cmd "mysqladmin ping -ppass"
+          --health-interval 10s
+          --health-start-period 10s
+          --health-timeout 5s
+          --health-retries 10
       postgres10:
         image: postgres:10
         env: