Fix logging delimiter parameterization

[nunomsantos]

Hi all,

While reading the classes and tests for the logging feature I noticed that the code introduced in pull request #4745 to add the improvement requested on #4734 is not working as intended.
This has not been noticed by the existing tests because they were using a constructor that would not pass through the problematic code.

Currently, when registering the LoggingFeature and setting the LoggingFeature.LOGGING_FEATURE_SEPARATOR property, the empty constructor is called, which calls other constructors with nulls and so on.

Eventually we reach the constructor using a LoggingFeatureBuilder, where the arguments are set to be passed to the last constructor.
There, the builder is also set with the default separator, which later causes the following code to ignore the configuration properties on configureBuilderParameters(...) .

final String filterSeparator = CommonProperties.getValue(/* read config from properties */);
// ...
// Config read from properties is never set
builder.separator = builder.separator == null ? filterSeparator : builder.separator;

Since the builder is initially set with the default separator, it is never overridden by the configurations.
The fix is just to remove the line setting the DEFAULT_SEPARATOR on the builder before passing to the last constructor.

I guess a conversation could be had about the other configurations: anything set as non-null in the builder cannot be overridden by configurations later; but that's likely okay because those other constructors are only used in tests and the empty constructor just sets everything as null.

[nunomsantos]

Hi, @jansupol. Not sure if I need to request a review but I don't see how I can do that in the UI.