The print-problems output order should be stable

[mtelka]

I run make update and then oi-pkg-checker run once a day. After that I save the print-problems output to a file. I noticed that the print-problems output could differ after the new run even there are no new problems found:

$ diff log/problems.2024-08-11_00:50:00 log/problems.2024-08-12_00:50:00 | head
656d655
< [WARN] package predicate=pkg:/runtime/go-8 doesn't exist, but is required by package image/graphviz (runtime, conditional)
657a657
> [WARN] package predicate=pkg:/runtime/go-8 doesn't exist, but is required by package image/graphviz (runtime, conditional)
698d697
< [ERROR] renamed package SUNWsfwdemo needs renamed package SUNWnet-snmp-doc
699a699
> [ERROR] renamed package SUNWsfwdemo needs renamed package SUNWnet-snmp-doc
721d720
< [ERROR] renamed package runtime/nodejs needs renamed package runtime/nodejs-10
$

When I sort the log then there are no differences:

$ diff <(sort log/problems.2024-08-11_00:50:00) <(sort log/problems.2024-08-12_00:50:00)
$

It would be great if the print-problems output does not change after the oi-pkg-checker run when there are no changes in the list of the problems.

Thank you.