Force a minimum version of Template::Toolkit

Version 3.004 fixes the CVE-2019-19781 security vulnerability.

https://www.mdsec.co.uk/2020/01/deep-dive-to-citrix-adc-remote-code-execution-cve-2019-19781/ describes the problem.

https://www.tenable.com/blog/cve-2019-19781-exploit-scripts-for-remote-code-execution-vulnerability-in-citrix-adc-and summarises its impact in another product.

Makefile.PL

@@ -52,6 +52,7 @@ our %prereq_pm = (
     'PDF::Table'                                => 0.11.0,
     'Session::Token'                            => 0,
     'String::CamelCase'                         => 0,
+    'Template'                                  => 3.004,
     'Test::MockTime'                            => 0,
     'Test::More'                                => 0,
     'Text::Autoformat'                          => 0,