Web socket updates

[IronGauntlets]

This PR introduces the most recent changes to websocket specs, please see each commit.

Todo:

• Fix sending of pending events. Currently, only when a new block is added the latest events are sent, however, there cannot be any duplicates and we need to make sure that the events are sent once the pending block is updated.
• Add subscription block id, so users cannot call ws subscription with blockID = pending.
• Add max websocket connections

[codecov]

Codecov Report

Attention: Patch coverage is 71.09375% with 37 lines in your changes missing coverage. Please review.

Project coverage is 74.38%. Comparing base (daeb674) to head (838719f).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
rpc/subscriptions.go	60.67%	33 Missing and 2 partials ⚠️
sync/sync.go	66.66%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2409      +/-   ##
==========================================
- Coverage   74.60%   74.38%   -0.23%     
==========================================
  Files         113      113              
  Lines       13052    13136      +84     
==========================================
+ Hits         9738     9771      +33     
- Misses       2583     2627      +44     
- Partials      731      738       +7     

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[rodrigo-pino]

LGTM overall, just some nitpicks

[AnkushinDaniil]

First round of review, I'll continue later

[rodrigo-pino]

LGTM