fix(core-json-rpc): avoid getting stuck on a unresponsive peer by picking a random one each time

[faustbrian]

Summary

Select a random peer every time we send a request and try to do so up to 3 times before giving up.

What kind of change does this PR introduce?

• Bugfix
• New feature
• Refactoring / Performance Improvements
• Build-related changes
• Documentation
• Tests / Continuous Integration
• Other, please describe:

Does this PR introduce a breaking change?

• Yes
• No

Does this PR release a new version?

• Yes
  • All tests are passing
  • All benchmarks are passing without any major regressions
  • Sync from 0 works on mainnet
  • Sync from 0 works on devnet
  • Starting a new network and forging on it work
  • Explorer is fully functional
  • Wallets are fully functional
• No

Checklist

• I have read the CONTRIBUTING documentation
• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

[ghost]

The ci/circleci: test-node11-integration-0 job is failing as of b813ef8bdaaf298f2bbf67a3db96002975434cd4. Please review the logs for more information.

Once you've pushed the fixes, the build will automatically re-run. Thanks!

[codecov-io]

Codecov Report

Merging #2491 into master will increase coverage by 0.03%.
The diff coverage is 88.88%.

@@            Coverage Diff             @@
##           master    #2491      +/-   ##
==========================================
+ Coverage   66.07%   66.11%   +0.03%     
==========================================
  Files         400      400              
  Lines        8614     8602      -12     
  Branches      436      436              
==========================================
- Hits         5692     5687       -5     
+ Misses       2877     2870       -7     
  Partials       45       45

Impacted Files	Coverage Δ
...ges/core-json-rpc/src/server/services/processor.ts	61.9% <ø> (-3.32%)	⬇️
.../core-json-rpc/src/server/methods/blocks/latest.ts	100% <100%> (ø)	⬆️
...json-rpc/src/server/methods/blocks/transactions.ts	100% <100%> (ø)	⬆️
...n-rpc/src/server/methods/transactions/broadcast.ts	90.9% <100%> (ø)	⬆️
...es/core-json-rpc/src/server/methods/blocks/info.ts	100% <100%> (ø)	⬆️
...e-json-rpc/src/server/methods/transactions/info.ts	100% <100%> (ø)	⬆️
...son-rpc/src/server/methods/wallets/transactions.ts	100% <100%> (ø)	⬆️
...s/core-json-rpc/src/server/methods/wallets/info.ts	100% <100%> (ø)	⬆️
...kages/core-json-rpc/src/server/services/network.ts	87.5% <85%> (+13.69%)	⬆️

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