Bump tests to v1.1.0-beta.2 (#2481)
Bump tests to v1.1.0-beta.2 (#2481)

## Proposed Changes

Bump spec tests to v1.1.0-beta.2, for conformance with the latest spec release: https://github.com/ethereum/eth2.0-specs/releases/tag/v1.1.0-beta.2

## Additional Info

We already happen to be compatible with the latest spec change that requires sync contributions to have at least one bit set. I'm gonna call it foresight on @realbigsean's part :sunglasses:

https://github.com/sigp/lighthouse/blob/6e3ca48cb934a63cafdc940068825a48cba740d1/beacon_node/beacon_chain/src/sync_committee_verification.rs#L285-L288




sigp/lighthouse,sigp/lighthouse,sigp/lighthouse,sigp/lighthouse