feat(congestion_control) - relax congestion control

[wacban]

As per zulip discussion congestion control seems to be too aggressive.

This is relaxing two parameters:

• The max gas in the delayed receipts queue increased twofold-> this will allow the queue to grow larger and buffer more receipts to handle spikes in traffic better. The tradeoff is that the queue will be larger and the transaction processing time will be slower during those periods.
• The reject_tx_congestion_threshold bumped from 50% to 70%. It means that new transactions will only be rejected once the congestion level reaches 70%.

Both parameters are picked pretty arbitrarily and there is no science behind it.

I am not increasing the outgoing or memory limits as they don't seem to be the bottleneck.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 71.61%. Comparing base (8ba5ed1) to head (f22713c).
Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #12241      +/-   ##
==========================================
- Coverage   71.61%   71.61%   -0.01%     
==========================================
  Files         836      836              
  Lines      167418   167423       +5     
  Branches   167418   167423       +5     
==========================================
- Hits       119903   119892      -11     
- Misses      42283    42297      +14     
- Partials     5232     5234       +2     

Flag	Coverage Δ
backward-compatibility	0.16% <0.00%> (ø)
db-migration	0.16% <0.00%> (ø)
genesis-check	1.25% <0.00%> (-0.01%)	⬇️
integration-tests	38.84% <57.14%> (-0.02%)	⬇️
linux	71.27% <100.00%> (+<0.01%)	⬆️
linux-nightly	71.20% <100.00%> (-0.01%)	⬇️
macos	54.27% <100.00%> (+0.02%)	⬆️
pytests	1.57% <0.00%> (-0.01%)	⬇️
sanity-checks	1.37% <0.00%> (-0.01%)	⬇️
unittests	65.38% <100.00%> (-0.01%)	⬇️
upgradability	0.21% <0.00%> (ø)

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

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.