Mention Test2 with regard to OTOBO specific modules

that are located in Kernel/cpan-lib

Kernel/cpan-lib/README.md

@@ -65,8 +65,11 @@ The reason why specific files are not included in the bundle is not always evide
 
 ### Add files that do no originate from CPAN or are modified by OTOBO
 
+These are Perl modules that belong to OTOBO but have to be in a specific namespace.
+
     cp -r Devel/REPL local/lib/perl5/Devel                # the plugins Devel::REPL::Plugin::OTOBO is not on CPAN
     cp -r Plack local/lib/perl5/Plack                     # the Plack plugins are not on CPAN
+    cp -r Test2 local/lib/perl5/Test2                     # the OTOBO specific Test2::Require modules
     cp -r HTML/Scrubber.pm local/lib/perl5/HTML/Scrubber  # with OTOBO specific modifications
 
 ### Install missing modules