tests: fix sortdict doctest with Python 3.12
The output of OrderedDict changed to use plain dict syntax:
$ python3.11 -c "import collections;print(collections.OrderedDict([('a', 0), ('b', 1)]))"
OrderedDict([('a', 0), ('b', 1)])
$ python3.12 -c "import collections;print(collections.OrderedDict([('a', 0), ('b', 1)]))"
OrderedDict({'a': 0, 'b': 1})
Test issue2761
$ hg init repo
$ cd repo
$ touch to-be-deleted
$ hg add
adding to-be-deleted
$ hg ci -m first
$ echo a > to-be-deleted
$ hg ci -m second
$ rm to-be-deleted
$ hg diff -r 0
Same issue, different code path
$ hg up -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ touch does-not-exist-in-1
$ hg add
adding does-not-exist-in-1
$ hg ci -m third
$ rm does-not-exist-in-1
$ hg diff -r 1