cpanm cannot look for Perl modules from root directories
without sudo so it creates '~/perl5/' and look for Perl modules in there.
Whether this directory existed before running cpanm or not,
cpanm returns a warning to advice the user to setup local::lib
in order to use modules in '~/perl5/' and exits with error code 0.
Each line in the warning always starts with '!'.
Display this warning to the user.
Continue parsing the version number if the warning can be ignored
because lines that are not prefixed with '!' are valid output.
Fix#11858
a1d6c2f5c9
