Fix minor typo in SYNOPSIS example code comment

Author: paultcochrane

Changes

@@ -1,6 +1,7 @@
 Revision history for WWW::Mechanize
 
 {{$NEXT}}
+    - Fix minor typo in SYNOPSIS example code comment (GH#379) (Paul Cochrane)
 
 2.18      2024-01-30 14:29:44Z
     [FIXED]

lib/WWW/Mechanize.pm

@@ -34,7 +34,7 @@ be queried and revisited.
         button    => 'Search Now'
     );
 
-    # Enable strict form processing to catch typos and non-existant form fields.
+    # Enable strict form processing to catch typos and non-existent form fields.
     my $strict_mech = WWW::Mechanize->new( strict_forms => 1);
 
     $strict_mech->get( $url );