Make flag enums have singular names only (no plural name aliases)

The plural name aliases for flag enums in PySide6 are redundant. Let me demonstrate this with an example copied from my CLI.

>>> from PySide6.QtCore import Qt
>>> Qt.TextInteractionFlags
<flag 'TextInteractionFlag'>

The plural name of the `TextInteractionFlags` flag enum apparently exists as an alias for the singular name of the same flag enum `TextInteractionFlag`. This is redundant.

But something interesting happens. If I have `Qt.TextInteractionFlags` in my VSCode IDE, then `Qt` is immediately marked with a red squiggly line, because I use the mypy extension. When I hover over this marked `Qt` text, a pop-up dialog window shows a hint that `"Type[Qt]" has no attribute "TextInteractionFlags"`.

This is strange, because using the plural name of the flag enum in the CLI (as demonstrated above) responds with the singular name of the same flag enum, so there must be an alias defined somewhere; otherwise, an `AttributeError` would have been raised, of course.

I searched the whole `QtCore.pyi` file and haven't found `TextInteractionFlags` in the `Qt` namespace, I found only `TextInteractionFlag`.

I have 3 questions now:

1. Where are those aliases defined?
2. Is it safe to use such aliases?
3. Will such aliases be removed in the future?

The PySide6 documentation lists only the singular names of the flag enums without listing their plural name aliases (such as `Qt.TextInteractionFlags`), but the plural name aliases must exist somewhere. Are those aliases kept for backwards compatibility only and will be removed in the future and are not documented for this very same reason?

The Qt documentation, however, is a different story. It, for example, lists the plural name as the flags of `Qt::TextInteractionFlags` enum and lists the singular name as an enum of `Qt::TextInteractionFlag`. Redundant, indeed. Or am I missing something?

Why is there such a mess? I suggest to only have one name for flag enums, the singular name. I honestly believe that all plural name aliases should be removed in Qt and consequently in PySide (and in PyQt, too). I'd just stick with singular names for the flag enums, simple and straightforward.

I have, however, read (can't rememeber where) that aliases (in Qt, I believe) such as `Qt::AlignLeft` will be removed in favor of `Qt::AlignmentFlag::AlignLeft`. But here is yet another mess: `Qt::Alignment` is an alias for `Qt::AlignmentFlag`, so it is the same if you use `Qt::Alignment::AlignLeft`.

There is no end to this mess. I wish Qt finally unifies this some day and removes all those "convenient" aliases which, in reality, only create ambiguity. This applies to PySide and PyQt as well.