Date-time with missing timezone minutes offset is considered valid in v3.0.1

I have a JSON schema as below

```
"testDate": {
  "type": "string",
  "format": "date-time"
}
``` 

The below date which has a missing minute offset which is considered valid
```
"testDate":  "2023-12-11T23:03:23.568+09"
```

I am using the below dependencies:

package.json:
```
"ajv": "^8.17.1",
"ajv-formats": "^3.0.1"

```

