[german][time] dayofMonth monthAsNumber at timeOfDay not detecting

Hi,

i really love Duckling, but one datetime parsing isnt quite right in german:
"dayofMonth monthAsNumber at timeOfDay" for example: `am vierten achten um dreizehn uhr`

should return `2022-08-04T13:00:00.000-07:00`

but returns:
```[
{
"body": "am vierten",
"start": 0,
"value": {
"values": [
{
"value": "2022-08-04T00:00:00.000-07:00",
"grain": "day",
"type": "value"
},
{
"value": "2022-09-04T00:00:00.000-07:00",
"grain": "day",
"type": "value"
},
{
"value": "2022-10-04T00:00:00.000-07:00",
"grain": "day",
"type": "value"
}
],
"value": "2022-08-04T00:00:00.000-07:00",
"grain": "day",
"type": "value"
},
"end": 10,
"dim": "time",
"latent": false
},
{
"body": "achten um dreizehn uhr",
"start": 11,
"value": {
"values": [
{
"value": "2022-08-08T13:00:00.000-07:00",
"grain": "hour",
"type": "value"
},
{
"value": "2022-09-08T13:00:00.000-07:00",
"grain": "hour",
"type": "value"
},
{
"value": "2022-10-08T13:00:00.000-07:00",
"grain": "hour",
"type": "value"
}
],
"value": "2022-08-08T13:00:00.000-07:00",
"grain": "hour",
"type": "value"
},
"end": 33,
"dim": "time",
"latent": false
}
]```

Reproduce the German input `am vierten achten um dreizehn uhr` through Duckling's time parser and compare the two returned spans with the expected single datetime. Inspect the German time-parsing rules and existing related tests; done means the expression is detected as `2022-08-04T13:00:00.000-07:00` rather than separate date and time results.

Written by the indexing model from the issue text.