* prysm-4757 remove proto.Clone() in favor of existing getters.Copy* methods
* prysm-4757 added a bunch of copy methods, and broke some tests
* squash commits
fix tests and getter implementations
remove usage of CopySignedBeaconBlock from ReceiveBlockNoVerify
* correctly copy Deposit proof and remove proto.clone() again
* Merge branch 'master' into prysm-4757-no-proto-clone
* Merge branch 'master' into prysm-4757-no-proto-clone
* Fix for comments, inline possible function calls
* Merge branch 'master' of https://github.com/prysmaticlabs/Prysm into prysm-4757-no-proto-clone
* Merge branch 'master' into prysm-4757-no-proto-clone
* updated with feedback from review
* Merge branch 'master' into prysm-4757-no-proto-clone
* Merge branch 'master' into prysm-4757-no-proto-clone
* Merge branch 'master' into prysm-4757-no-proto-clone
