Time between heartbeats at bootstrap

[sstanculeanu]

Reasoning behind the pull request

• during bootstrap, heartbeats will be used to keep track of trie sync progress. Currently, the time between sends is the same as regular heartbeats, 5 min, which may be too much for a proper progress bar

Proposed changes

• added new config value

Testing procedure

• start a node on testnet. Either check logs for heartbeat message sent to be ~1 min, either check https://testnet-gateway.multiversx.com/node/heartbeatstatus and make sure the numTrieNodesReceived for your node increases each ~minute during trie sync
• after bootstrap, the same log should be after ~5min, and numTrieNodesReceived 0

Pre-requisites

Based on the Contributing Guidelines the PR author and the reviewers must check the following requirements are met:

• was the PR targeted to the correct branch?
• if this is a larger feature that probably needs more than one PR, is there a feat branch created?
• if this is a feat branch merging, do all satellite projects have a proper tag inside go.mod?

[iulianpascalau]

do we need to have this set to 1 minute on the public testnets & mainnet? The original code used HeartbeatTimeBetweenSendsInSec which was set to 5 minutes.

[sstanculeanu]

exactly, this was the reason behind the PR. While testing on public testnet, I realized that 5 min with no feedback would be too much