recognitionService.recognize without limit parameter results in malformed url

**Describe the bug**
If you call `recognize` without limit parameter the url is not valid and a 400 is returned from the REST API.

**To Reproduce**
```ts
try {
const result = await recognitionService.recognize(path_toTestImage, {
face_plugins: 'landmarks,gender,age',
det_prob_threshold: 0.95,
status: true
});
} catch (e) {
console.error('Error while recognize' + e.message);
console.error(e.config.url); // <-- comes here. not good
}
```
Prints
`http://localhost:8000/api/v1/recognition/recognize?det_prob_threshold=0.95?face_plugins=landmarks,gender,age?status=true`

**Expected behavior**
If I do not pass limit it should use a default or build a valid url.
Should be
`http://localhost:8000/api/v1/recognition/recognize?det_prob_threshold=0.95&face_plugins=landmarks,gender,age&status=true`

Maybe other webservers/backends do not care but I use the docker-compose version from https://github.com/exadel-inc/CompreFace/releases/tag/v1.0.0

Start at the recognitionService.recognize entry point and trace how its optional parameters are serialized into the request URL. Reproduce the call without limit, then verify that query parameters are joined correctly and the resulting REST request is accepted.

Scritto dal modello di indicizzazione a partire dal testo della issue.