fix nnictl trial kill (#1259)

tools/nni_cmd/url_utils.py

@@ -67,7 +67,7 @@ def trial_jobs_url(port):
 
 def trial_job_id_url(port, job_id):
     '''get trial_jobs with id url'''
-    return '{0}:{1}{2}{3}/:{4}'.format(BASE_URL, port, API_ROOT_URL, TRIAL_JOBS_API, job_id)
+    return '{0}:{1}{2}{3}/{4}'.format(BASE_URL, port, API_ROOT_URL, TRIAL_JOBS_API, job_id)
 
 
 def export_data_url(port):
@@ -87,4 +87,4 @@ def get_local_urls(port):
         for addr in info:
             if AddressFamily.AF_INET == addr.family:
                 url_list.append('http://{}:{}'.format(addr.address, port))
-    return url_list
\ No newline at end of file
+    return url_list