Drop unnecessary and outdated version requirement of DBIx::SearchBuilder

The updated version has already been specified in etc/cpanfile.

Besides, perl 5.40 doesn't like the weird version string "1.40"(numeric 1.40
is ok) and issues a warning:

    Attempt to call undefined import method with arguments ("1.40") via package "DBIx::SearchBuilder"

Author: sunnavy

lib/RT/SearchBuilder.pm

@@ -71,7 +71,7 @@ use 5.010;
 use base qw(DBIx::SearchBuilder RT::Base);
 
 use RT::Base;
-use DBIx::SearchBuilder "1.40";
+use DBIx::SearchBuilder;
 
 use Scalar::Util qw/blessed/;