Delete existing dstat files during teardown

Currently dstat-csv.log file is only deleted during teardown.
other dstat files dstat.{html, txt} if stays from the previous run
then it will eat up the space on the system leading to disk_full
issue in the job.

Cleaning up these files during teardown process, will avoid such
issues.

Signed-off-by: Chandan Kumar (raukadah) <chkumar@redhat.com>
Change-Id: Ide52cf94eb94d22cf8b789d041a0d260afad81fb

roles/environment/teardown/tasks/main.yml

@@ -53,7 +53,13 @@
       become: true
 
 - name: Delete any existing dstat log file
-  file: dest=/var/log/extra/dstat-csv.log state=absent
+  file:
+    dest: "/var/log/extra/{{ item }}"
+    state: absent
+  with_items:
+    - dstat-csv.log
+    - dstat.html
+    - dstat.txt
   become: true
 
 - name: Delete OVS Bridges