fix package.json format

[lbhfuture]

yarn build error with message:

⨯ node_modules.Dependency.Dependencies: ReadMapCB: expect { or n, but found ", error found in #10 byte of ...|encies": ""
}|..., bigger context ...|"
    },
    "homepage": "",
    "dependencies": ""
}|...

Because of a invalid format of dependencies in package.json, it should be a object {}, as yours is string "".