Add runtime to 3.5 schema

Signed-off-by: Andy Neff <[email protected]>

Author: andyneff

compose/config/config_schema_v3.5.json

@@ -228,6 +228,7 @@
         "privileged": {"type": "boolean"},
         "read_only": {"type": "boolean"},
         "restart": {"type": "string"},
+        "runtime": {"type": "string"},
         "security_opt": {"type": "array", "items": {"type": "string"}, "uniqueItems": true},
         "shm_size": {"type": ["number", "string"]},
         "secrets": {