In cases where a string is used both for a visible label and a screen reader text label, the screen reader text should never be different from the visible label. To help ensure this doesn't happen, use only a single string. The associated screen reader text comments are no longer required.
This is also true for a few cases where there are strings in contexts where variables can't be used. In these cases, the screen reader text comments are also removed.
Props sabernhardt, swissspidy, audrasjb, joedolson.
Fixes#63620.
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