addKeyword expects 2 paramters according to typescript but give a deprecation error

addKeyword wants a type and the config as two parameters. When I do that I am getting an error `these parameters are deprecated, see docs for addKeyword`.

Using 8.11.0 (latest fasitfy)

works but has typescript error:
```
ajv.addKeyword({
keyword: 'isFileType',
type: 'object',
compile: (schema, parent, it) => {
parent.type = 'file';
delete parent.isFileType;
return () => true;
},
});
```

no typescript error but deprecation error:
```
ajv.addKeyword( 'isFileType', {
compile: (schema, parent, it) => {
parent.type = 'file';
delete parent.isFileType;
return () => true;
},
});
```