fix: aria-label for edit and drag block button

[sabrina-bongiovanni]

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Closes #5269

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Needs cherrypick on 18

[pnicolli]

Just a conflict missing then I think this is good to go

[davisagli]

This looks like a good improvement, just needs a couple adjustments.

[giuliaghisini]

@davisagli @pnicolli @sneridagh is it possibile to cherrypick this pr on 18.x.x?