feat: support depends_on

This PR supports the extended pattern of `depends_on`. If the short version of
`depends_on` is defined, it will be migrated to the extended version like the
example below:

```yaml
services:
  web:
    depends_on
    - database

services:
  web:
    depends_on:
      database:
        condition: service_started
```

All three types of merging strategies are supported.

renovate.json

@@ -30,8 +30,7 @@
       "matchManagers": [ "gomod" ],
       "matchPackageNames": [
         "gopkg.in/yaml.v2"
-      ],
-      "matchUpdateTypes": [ "major" ]
+      ]
     }
   ],
   "postUpdateOptions": [