Fix check_by_ssh test for non-Bash login shells

In the C shell and in the Z shell, the "?" character must be quoted or
backslash-escaped in order to use it verbatim.  Therefore, a command
such as

	check_by_ssh -H test.example.com -l joe echo huh?

might fail, depending on joe's login shell on test.example.com.

Just to make sure, this commit removes most punctuation characters from
our test strings.

plugins/t/check_by_ssh.t

@@ -27,11 +27,11 @@ plan skip_all => "SSH_HOST and SSH_IDENTITY must be defined" unless ($ssh_servic
 plan tests => 42;
 
 # Some random check strings/response
-my @responce = ('OK: Everything is fine!',
-                'WARNING: Hey, pick me, pick me!',
-                'CRITICAL: Shit happens...',
-                'UNKNOWN: What can I do for ya?',
-                'WOOPS: What did I smoke?',
+my @responce = ('OK: Everything is fine',
+                'WARNING: Hey, pick me, pick me',
+                'CRITICAL: Shit happens',
+                'UNKNOWN: What can I do for ya',
+                'WOOPS: What did I smoke',
 );
 my @responce_re;
 my @check;