Don't fall off the end of perl functions

This complies with the perlcritic policy
Subroutines::RequireFinalReturn, which is a severity 4 policy. Since we
only currently check at severity level 5, the policy is raised to that
level until we move to level 4 or lower, so that any new infringements
will be caught.

A small cosmetic piece of tidying of the pgperlcritic script is
included.

Mike Blackwell

Discussion: https://postgr.es/m/CAESHdJpfFm_9wQnQ3koY3c91FoRQsO-fh02za9R3OEMndOn84A@mail.gmail.com

src/pl/plperl/plc_perlboot.pl

@@ -62,6 +62,7 @@ sub ::encode_array_constructor
 		(my $msg = shift) =~ s/\(eval \d+\) //g;
 		chomp $msg;
 		&::elog(&::WARNING, $msg);
+		return;
 	}
 	$SIG{__WARN__} = \&plperl_warn;
 

src/pl/plperl/text2macro.pl

@@ -99,4 +99,5 @@ sub selftest
 	warn "Test string: $string\n";
 	warn "Result     : $result";
 	die "Failed!" if $result ne "$string\n";
+	return;
 }