Revert to default FAIL2BAN findtime for SSH jail

I propose that the default 600s/10minute find time is a better test duration for this ban. The altered 120s findtime sounds reasonable until you consider that attackers can simply throttle to 3 attempts per minute and never be banned.

The remaining non default jail settings of maxretry = 7 and bantime = 3600 I believe are good.

conf/fail2ban/jail.local

@@ -4,7 +4,6 @@
 
 [ssh]
 maxretry = 7
-findtime = 120
 bantime = 3600
 
 [ssh-ddos]