Remove yielded link-to component from <BsNav>

[jelhan]

Some time ago we renamed the yielded property of <BsNav> from link-to to linkTo. But we kept the original one to not introduce a breaking change: https://github.com/kaliber5/ember-bootstrap/blob/31d43678ac0fa52d5bd36e3d8e570d1b9b46d0b4/addon/components/bs-nav.hbs#L5-L6

We may want to remove it as part of next major.

[simonihmig]

Do you think it's worth it? Or should we just keep it for dev convenience. After all, this requires some changes for users (we could help via our codemod - but do we have time to work on this?), and the maintenance benefit seem low (not much significant tech debt by keeping this?).

[jelhan]

Wondering if we should revisit the decision for v6. I feel the arguments are still the same. But after such a long time most consumers may have refactored away from it anyways?