Replace lucene.testSettings.config references with lucene.testsettings.json

[paulirwin]

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Replace lucene.testSettings.config references with lucene.testsettings.json

Fixes #997

Description

There were still some places in comments where we were referencing lucene.testSettings.config as the file name for setting your seed/culture, when it should be lucene.testsettings.json. This does a solution-wide find and replace for those occurrences in comments.