learn: use Perl 5.12

No `unicode_strings' feature dependencies, here, so it's safe to
get rid of the extra overhead required in loading strict.pm.

diff --git a/script/public-inbox-learn b/script/public-inbox-learn
index 12a82de99e7de415404ffa326ac6188fe393d6ad..b7f98dcc96fa64300f7f3fcfce576be5142e9fb0 100755 (executable)
--- a/script/public-inbox-learn
+++ b/script/public-inbox-learn
@@ -20,7 +20,7 @@ options:
 
 See public-inbox-learn(1) man page for full documentation.
 EOF
-use strict;
+use v5.12;
 use PublicInbox::Config;
 use PublicInbox::InboxWritable;
 use PublicInbox::Eml;