[TACACS] Add --no-pager to tacacs utils (#15491)

Summary: Add --no-pager to journalctl to display all logs at once, allowing grep to search through the output even when there are many logs.

tests/tacacs/utils.py

@@ -363,7 +363,7 @@ def log_exist(ptfhost, sed_command):
 
 
 def get_auditd_config_reload_timestamp(duthost):
-    res = duthost.shell("sudo journalctl -u auditd --boot | grep 'audisp-tacplus re-initializing configuration'")
+    res = duthost.shell("sudo journalctl -u auditd --boot --no-pager | grep 'audisp-tacplus re-initializing configuration'") # noqa E501
     logger.info("aaa config file timestamp {}".format(res["stdout_lines"]))
 
     if len(res["stdout_lines"]) == 0: