Update project postcodify to 1.8.4

libgrabber updated project postcodify to 1.8.4.

@kijin

### Metadata information

```json
{
  "metadata": {
    "packageManager": "github",
    "name": "postcodify",
    "repo": "kijin/postcodify",
    "files": {
      "basePath": "api",
      "include": ["search.min.js"],
      "exclude": []
    },
    "path": "/home/jsdelivr/files/jquery.postcodify",
    "localVersions": ["1.7.1", "1.8.1", "1.8.2", "1.8.3"],
    "remoteVersions": ["1.2.0", "1.2.1", "1.3.0", "1.4.2", "1.5.0", "1.5.1", "1.5.2", "1.5.3", "1.5.4", "1.5.5", "1.6.0", "1.7.0", "1.7.1", "1.8.0", "1.8.1", "1.8.2", "1.8.3", "1.8.4"],
    "branchVersions": []
  },
  "version": "1.8.4",
  "updated": true,
  "updatePath": "/home/jsdelivr/files/jquery.postcodify/1.8.4",
  "branch": "postcodify/1.8.4"
}
```