Make $@ safe in PPI

[schwern]

PPI has a bunch of uses of eval which do not localize $@ causing issues for us where $@ is lost.

Get PPI patched to protect $@ in the uses of eval.

Updating our PPI dependency to use that is in question as it will make Method::Signatures harder to use based on vendor supplied PPI packages which are likely to be out of date and it's a very low priority fix.