Update test_ro_disk.py (sonic-net#12913)

Fix ro disk test case generate garbled syslog and break loganalyzer issue.

#### Why I did it
Log rotate during ro disk may cause syslog file contains garbled characters.
These characters will break loganalyzer, to fix this issue, rotate again to cleanup syslog file.

#### How I did it
log rotate again after ro disk test case finish,

#### How to verify it
Pass all test case.

#### Description for the changelog
Fix ro disk test case generate garbled syslog and break loganalyzer issue.

tests/tacacs/test_ro_disk.py

@@ -191,6 +191,7 @@ def test_ro_disk(localhost, ptfhost, duthosts, enum_rand_one_per_hwsku_hostname,
         duthost.copy(src=conf_path, dest="/etc/rsyslog.d/000-ro_disk.conf")
 
         # To get file in decent size. Force a rotate
+<<<<<<< HEAD
 <<<<<<< HEAD
         log_rotate(duthost)
 =======
@@ -203,6 +204,9 @@ def test_ro_disk(localhost, ptfhost, duthosts, enum_rand_one_per_hwsku_hostname,
             else:
                 raise e
 >>>>>>> [TACACS] Handle log rotate failed issue (#12821)
+=======
+        log_rotate(duthost)
+>>>>>>> Update test_ro_disk.py (#12913)
 
         res = duthost.shell("systemctl restart rsyslog")
         assert res["rc"] == 0, "failed to restart rsyslog"