Prysm v5.0.0 compatibility

Compatibility with Prysm 5.x

Merge pull request #8 from stakefish/adaszko/list-block-headers-upgrade

Transition off removed GRPC endpoint BlockHeadersRequest

Changes:

 * Add a metric for tracking of blocks with no transactions
 * Security fixes

Fix eth2-monitor for Capella Hardfork (#2)

* Update packages

* Add CapellaBlock Capability and make programm exit if unknown hardfork block appears

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Co-authored-by: fkbenjamin <flo.liss@gmail.com>

* Support Bellatrix and post-merge

* Handle deposits per block activating newly deposited validators