Change id field passed to JobInfo from int to str

fixes aiidateam#29

The id field of JobInfo is expecting a str. In aiidateam#24 when parsing JSON
output of `hq job list` the json loads will use the int for the id
parsed directly. Wrong type causes the subtle issue that when job is
waiting it not get into QUEUED state, but immediatly finished and get
nothing to parse from output.

aiida_hyperqueue/scheduler.py

@@ -228,7 +228,7 @@ def _parse_joblist_output(self, retval: int, stdout: str, stderr: str) -> list:
         job_info_list = []
         for hq_job_dict in hq_job_info_list:
             job_info = JobInfo()
-            job_info.job_id = hq_job_dict["id"]
+            job_info.job_id = str(hq_job_dict["id"])    # must be str, if it is a int job will not waiting
             job_info.title = hq_job_dict["name"]
             stats: t.List[str] = [
                 stat for stat, v in hq_job_dict["task_stats"].items() if v > 0