Extensions should indicate if they are usable in Bands

[jsignell]

Either there should be a check mark to indicate that extensions are usable in bands or bands should be included in one of the parentheses:

The fields in the table below can be used in these parts of STAC documents:


- [ ] Catalogs
- [x] Collections
- [x] Item Properties (incl. Summaries in Collections)
- [x] Assets (for both Collections and Items, incl. Item Asset Definitions in Collections)
- [ ] Links

ref: https://github.com/stac-extensions/template/blob/82c71bf6fc8f905064786fe295a4051c105f5e6b/README.md?plain=1#L21C1-L27C12