Add host description when throwing MissedHeartbeatException

[laststem]

Proposed Changes

Adding a host description when throwing MissedHeartbeatException.
if there are two RabbitMQ Node for different purposes, but exception don't showing which node it is for.
sorry for english. thank you.

Types of Changes

• Bugfix (non-breaking change which fixes issue #NNNN)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation (correction or otherwise)
• Cosmetics (whitespace, appearance)

Checklist

• I have read the CONTRIBUTING.md document
• I have signed the CA (see https://cla.pivotal.io/sign/rabbitmq)
• All 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)
• Any dependent changes have been merged and published in related repositories

[michaelklishin]

Thank you for taking the time to contribute.

I don't find this particularly useful as node logs will in practice contain relevant information. @acogoluegnes WDYT?

[acogoluegnes]

This extra information does not make any harm, so I'm not opposed to merge this if it can help some users.

[michaelklishin]

I reworded the message and backported to 5.x.