Smaller input field for update notification groups

[MorrisJobke]

Fixes a paper cut from #2672 - cc @nextcloud/designers

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[mention-bot]

@MorrisJobke, thanks for your PR! By analyzing the history of the files in this pull request, we identified @nickvergessen, @LukasReschke and @blizzz to be potential reviewers.

[nickvergessen]

Well I don't care too much, I just made it longer, because the space is there and otherwise the height increases:

[LukasReschke]

I'd say let's keep the @nickvergessen approach then? 😃

[jancborchardt]

Sorry for the late reply:
In most cases it will likely stay only the administrators. So that case should look good, as it does now. If we want to improve it then ideally it is through dynamic width increase until it needs to wrap cause of the viewport ending. That probably involves some JS which is not really necessary there, so maybe it’s best to leave it like it is.