bug#34360: perl-mode doesn't respect certain EOF blocks

[積丹尼 Dan Jacobson]

Here perl-mode insists on moving my EOF block away from the margin as if
it needed to be indented. Type TAB on such lines to check.

for ( @{ $p->{result_data}->{channels} } ) {
    printf <<EOF,
%d new messages in https://example.nd/example/%d/chat/%s
EOF
      $_->{new_message_count}, $_->{example}->{example_no}, $_->{channel_id};
}

emacs-version "26.1"

(True, the user could also do printf "some
long
paragraph" too as a simpler working way.)