[User Story] - notation pull signatures

[dtzar]

As a user, I want to pull signatures from remote registry, using tag or digest references

Note: decision by group to push past RC-1, since notation verify does pull automatically, and this really becomes more relevant once verifying local artifacts is enabled.

• Update notation pull command #233

[yizha1]

As discussed in the community meeting on Nov 4, 2024, move this issue to the future milestone