fix(ci): Allow extra lookahead blocks in the verifier, state, and block commit task queues

[teor2345]

Motivation

Full syncs are timing out on the main branch, with a lot of "synced block height too far ahead of the tip: dropped downloaded block" errors:
https://github.com/ZcashFoundation/zebra/actions/runs/3300574887/jobs/5458683486

Close #5420.

Solution

• Allow extra capacity in the verifier queue, state queue, or block commit task channel

This will increase Zebra's memory usage, users can reduce memory usage by reducing the configured lookahead limit.

Review

We can only test this change by merging it to main.

Reviewer Checklist

• Will the PR name make sense to users?
  • Does it need extra CHANGELOG info? (new features, breaking changes, large changes)
• Are the PR labels correct?
• Does the code do what the ticket and PR says?
• How do you know it works? Does it have tests?

[codecov]

Codecov Report

Merging #5465 (dde1f24) into main (a2dba8c) will decrease coverage by 0.07%.
The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5465      +/-   ##
==========================================
- Coverage   79.12%   79.04%   -0.08%     
==========================================
  Files         308      308              
  Lines       39324    39324              
==========================================
- Hits        31115    31084      -31     
- Misses       8209     8240      +31     

[oxarbitrage]

looks good, thanks.