Fix minor SonarQube smells

[artembilan]

See Sonar report for the current main: https://sonar.spring.io/project/issues?id=org.springframework.integration%3Aspring-integration%3Amain&resolved=false&severities=MINOR&types=CODE_SMELL

Mostly those smells are about a Magic Number rule violation.

In some places we indeed need to extract a constant for such a default value, but in other places it really would be better just to place a // NOSONAR comment after the code line to ignore it from Sonar analysis.

[trgpa]

I'm going to make a pull request on this issue soon.

[trgpa]

although this is not really related to the issue at hand but doesn't TestingUtilities.waitStopListening() wait up for 20 seconds instead of 10 as stated in the docs?

[artembilan]

I think we just missed to look into those JavaDocs when we adjusted a default timeout.
Sometime with heavy loaded environment 10 seconds is not enough to verify.
So, if you fix that JavaDoc in your PR, it would be great.

Thank you for being so precise!

[trgpa]

Unfortunately I can't just fix the JavaDocs to state that it defaults to 20 seconds. The problem is that the method actually waits up to delayArg * 2 milliseconds. To make it consistent with the other methods we have to revise several method calls so I think I will ignore this for now.

[artembilan]

Unfortunately I can't just fix the JavaDocs to state that it defaults to 20 seconds.

OK, @trungPa . Would you mind then to raise a separate special issue for this TestingUtilities inconsistency?
Thanks