Keep sort order when filtering lists sorted by date

[stefanhaller]

• PR Description

Keep the sort order stable when filtering lists of things sorted by date (branches, stashes, reflog entries).

• Please check if the PR fulfills these requirements

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• Code has been formatted (see here)
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• Docs (specifically docs/Config.md) have been updated if necessary
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Coverage summary from Codacy

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Coverage variation	Diff coverage
✅ -0.01% (target: -2.00%)	✅ 90.00%

Coverage variation details

	Coverable lines	Covered lines	Coverage
Common ancestor commit (c4eedec)	48114	40223	83.60%
Head commit (9f0b4d0)	48120 (+6)	40225 (+2)	83.59% (-0.01%)

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Diff coverage details

	Coverable lines	Covered lines	Diff coverage
Pull request (#3282)	20	18	90.00%

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[stefanhaller]

The argument of seeing the best match first in the suggestions view convinced me that it's not desirable to retain the sort order in all lists, but only in those where things are sorted by date.

However, suggestion lists are not affected by this change at all, as they are not using the FilteredListViewModel; they call FuzzySearch themselves (in suggestions_helper.go). Nevertheless, it convinced me that when things are sorted alphabetically, it makes little sense to retain this ordering, and sorting by best match is better.

So I made this configurable, and chose to retain the sort order only in the local and remote branches views (but only when sorting by date or recency), and in the stashes and reflog views. And in the menu view, because we can then keep the section headers in the keybindings menu, which is very useful. All other views now sort by best match as before.

[stefanhaller]

@jesseduffield When we tested this today, it didn't work correctly when changing the sort order for local branches. The reason was that I was testing my local integration branch that had a much older version of this PR, which didn't make the distinction of alphabetical vs. by date yet. I tested this one again, works as expected.

Apart from that, we decided to go with this version and see if people complain, so I'm going to merge now.