Fix 003_extrafiles.pl test for the Windows

File::Find converts backslashes to slashes in the newer Perl versions.
See: Perl/perl5@414f14d

So, do the same conversion for Windows before comparing paths. To
support all Perl versions, always convert them on Windows regardless of
the Perl's version.

Author: Nazir Bilal Yavuz <byavuz81@gmail.com>

Backpatch to all live branches

Author: adunstan

src/bin/pg_rewind/t/003_extrafiles.pl

@@ -67,6 +67,19 @@ sub run_test
 		},
 		$test_master_datadir);
 	@paths = sort @paths;
+
+	# File::Find converts backslashes to slashes in the newer Perl
+	# versions. To support all Perl versions, do the same conversion
+	# for Windows before comparing the paths.
+	if ($PostgreSQL::Test::Utils::windows_os)
+	{
+		for my $filename (@paths)
+		{
+			$filename =~ s{\\}{/}g;
+		}
+		$test_primary_datadir =~ s{\\}{/}g;
+	}
+
 	is_deeply(
 		\@paths,
 		[