[#820] Enable checkstyle for streampipes-config and add suppress support for checkstyle

[RobertIndie]

Purpose

Master Issue: #820

• Enable checkstyle for streampipes-config
• Add suppress support for checkstyle, now we can use this way to suppress the style check before the code:

@SuppressWarnings("checkstyle:{Rule-name}")
...

I found that there is an issue in the IDEA: https://youtrack.jetbrains.com/issue/IDEA-80495/Settings-Operation-sign-on-next-line-does-not-work-for-automatically-breaking-strings.
Therefore, we seem couldn't reformat the code according to the OperatorWrap rule automatically. Haven't found a good solution yet. We could only format it manually.

Remarks

PR introduces (a) breaking change(s): no

PR introduces (a) deprecation(s): no

[bossenti]

Really cool to have this decorator syntax 👍🏼