bbox-crs is still mentioned in core/commons.yaml

[NicolaiLolansen]

PR #64 removes all mentions of bbox-crs from core, except a descriptive text under bbox in cor/commons.yaml

stac-api-spec/core/commons.yaml

Line 521 in 0f1ff40

`bbox-crs`.

This should probably also be removed, as to not confuse users.

[philvarner]

Thanks for spotting this @NicolaiMogensen !