Add scenarios in integration tests relevant to lisk-p2p

[ishantiw]

Description

Add missing integration tests on lisk-p2p. Cover different scenarios like, for example, when a couple of nodes become unresponsive due to some reason, other nodes connected should be able to detect and update their network status gracefully.

Review checklist

• The PR resolves #INSERT_ISSUE_NUMBER
• All new code is covered with unit tests
• All new code was formatted with Prettier
• Linting passes
• Tests pass
• Commit messages follow the commit guidelines
• Documentation has been added/updated

[ishantiw]

I will add test cases related to the custom selection function. Issue created #1131