perf/aggregate: sort JSON fields in output

It is much easier to diff the output against a previous
one when the fields are sorted.

Helped-by: Philip Oakley <[email protected]>
Signed-off-by: Christian Couder <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: chriscool

t/perf/aggregate.perl

@@ -253,7 +253,7 @@ sub print_codespeed_results {
 		}
 	}
 
-	print to_json(\@data, {utf8 => 1, pretty => 1}), "\n";
+	print to_json(\@data, {utf8 => 1, pretty => 1, canonical => 1}), "\n";
 }
 
 binmode STDOUT, ":utf8" or die "PANIC on binmode: $!";