Modify `EpochLookup` to handle epoch fallback trigger condition

[jordanschalm]

This PR modifies EpochLookup to respond to epoch fallback triggers explicitly via protocol event. The modified structure is based on the consensus committee changes in https://github.com/onflow/flow-go/pull/2782.

• EpochLookup implements Component
• EpochLookup responds to appropriate protocol events and caches static data rather than querying state each time

[codecov-commenter]

Codecov Report

Merging #2927 (c9d42c9) into feature/active-pacemaker (6a39c8c) will increase coverage by 0.07%. The diff coverage is 72.60%.

@@                     Coverage Diff                      @@
##           feature/active-pacemaker    #2927      +/-   ##
============================================================
+ Coverage                     54.01%   54.09%   +0.07%     
============================================================
  Files                           755      755              
  Lines                         70556    70653      +97     
============================================================
+ Hits                          38113    38221     +108     
+ Misses                        29317    29296      -21     
- Partials                       3126     3136      +10     

Flag	Coverage Δ
unittests	54.09% <72.60%> (+0.07%)	:arrow_up:

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
utils/unittest/fixtures.go	0.00% <0.00%> (ø)
module/epochs/epoch_lookup.go	71.61% <73.61%> (+43.27%)	:arrow_up:
fvm/handler/contract.go	66.90% <0.00%> (+0.71%)	:arrow_up:
consensus/hotstuff/eventloop/event_loop.go	78.09% <0.00%> (+2.38%)	:arrow_up:
...s/hotstuff/votecollector/staking_vote_processor.go	84.21% <0.00%> (+3.15%)	:arrow_up:
insecure/orchestrator/corrupted_connection.go	82.35% <0.00%> (+7.84%)	:arrow_up:

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.