Add complete list of missing required values to constraint violation error

Description:

When a document is missing multiple required values, nuxeo client only returns the first missing value: https://github.com/nuxeo/nuxeo/blob/10.10/nuxeo-core/nuxeo-core-api/src/main/java/org/nuxeo/ecm/core/api/validation/DocumentValidationException.java#L33-L34

Repro Steps:

• Drop the attached jar into nxserver/plugins 
• Run curl command:

  curl -H "Content-Type: application/json" -XPOST -u Administrator:Administrator http://localhost:8080/nuxeo/api/v1/path/ -d '{ "entity-type":"document", "type": "test_required_value", "name":"docOne", "properties": {"dc:title":"docOne"}}'
  

Outcome:

{"entity-type":"exception","status":422,"message":"2 constraint violation(s) thrown. First one thrown on property test_required_value:requiredValue[0]: 'Value is required.', call DocumentValidationException.getViolations() to get the others"}

Expected outcome:

The error message should contain the complete list of missing required values