chore: Automate more static code checks

[valfirst]

Change list

It's better to prevent code style violations instead of fixing them. The aim of this PR is to automate checks for code style fixes from #2017.

Types of changes

What types of changes are you proposing/introducing to Java client?

• No changes in production code.
• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Details

• Enabled Checkstyle rules to cover all cases from fix: Fix Code style issues to match Java standards #2017.
• Fixed all leftovers.
• Checkstyle doesn't play well with Lombok (checkstyle not taking lombok generated code  checkstyle/checkstyle#13508, add support for Lombok private constructor checkstyle/checkstyle#2579), the easiest solution is to replace Lombok with native Java code.