Add services.txt to the logscraper download list

There is some interesting info in the services.txt log generated by
Devstack. It contains the systemctl status of all services on the host.

This would enable us to search for unhealthy service status such as:

  "ceph-mon[47381]: log_channel(cluster) log [WRN] : Health check
   update: 10 slow ops, oldest one blocked for 1982 sec, osd.0 has slow
   ops (SLOW_OPS)"

for investigation of CI job failures.

Change-Id: I9a5ffe86880f08cb0c8adb2cab155da3bea0187b

ansible/roles/logscraper/templates/download-list.yaml.j2

@@ -35,6 +35,9 @@ files:
     tags:
       - performance
       - devstack
+  - name: controller/logs/services.txt
+    tags:
+      - devstack
   # Nova and Placement
   - name: controller/logs/tempest_log.txt
     tags:
@@ -214,6 +217,10 @@ files:
       - devstack
       - syslog
       - multinode
+  - name: compute1/logs/services.txt
+    tags:
+      - devstack
+      - multinode
   - name: compute1/logs/screen-n-cpu.txt
     tags:
       - screen