Remove Serializable interface from Violation class and EventObject extension from AuditEvent

[rnveach]

Since we don't use serialization, we will remove this class being serializable as it is not serializable due to arg field.

Serialization was added at d2af4ac#diff-52efb9bb7c26b577e3885a9539eac7d5R42 titled Apply parts of patch #1952556 fixing some FindBugs bugs. Thanks to Travis Schneeberger.

http://git.net/ml/java.audit.checkstyle.devel/2008-04/msg00067.html

Findbugs does produce this error if I remove the serialization:

[INFO] Class com.puppycrawl.tools.checkstyle.api.AuditEvent defines non-transient non-serializable instance field localizedMessage [com.puppycrawl.tools.checkstyle.api.AuditEvent] In AuditEvent.java SE_BAD_FIELD

This is because AuditEvent is serialized through inheritance of EventObject.
Such inheritance also should be removed.

============

Now this is become why is AuditEvent serialized and need EventObject.

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Second problem of serialization:
Detected by IDEA inspection and Sonar Inspection Make "args" transient or serializable.
https://sonarcloud.io/project/issues?id=org.checkstyle%3Acheckstyle&issues=AW9t2w2MYD2QG1pPXIUJ&open=AW9t2w2MYD2QG1pPXIUJ

checkstyle/src/main/java/com/puppycrawl/tools/checkstyle/api/Violation.java

Lines 67 to 76 in 54616f6

	/**
	* Arguments for MessageFormat.
	*
	* @noinspection NonSerializableFieldInSerializableClass
	* @noinspectionreason NonSerializableFieldInSerializableClass - usage of
	* 'Serializable' for this api class
	* is considered as mistake now, but we do not break api without
	* good reason
	*/
	private final Object[] args;

Slightly related problem: #7488 (comment) but a different approach.

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PR Discussion resolution for second problem:

Changing args to something more serializable would be a huge break for whole Checkstyle. This would impact property files which use special properties of MessageFormat to format the argument into a meaningful display.

[nitishmalang]

please assign me i can work on this issue

[rnveach]

@nitishmalang This is already taken and has a PR awaiting review.

[romani]

Should we title issue something as Remove serializable interface from Violation class ?

[rnveach]

I am fine with that.

[nrmancuso]

Closed via #12675