TraceSourceLogger now takes exception into account(adds it to the log… (#42571)

TraceSourceLogger now takes exception into account(adds it to the log… (#42571)

* TraceSourceLogger now takes exception into account(adds it to the log message) even if formatter is not null

* Fixed a logical error, that would have added the exception twice to the log message when the formatter would have been null.

* Added tests for TraceSourceLogger.

* Removed unnecessary white-spaces.

* Make the TraceLogger output more "natural" (one line message)  and similar to SystemdConsoleFormatter.

* Update TraceSourceLoggerTest.cs

* Update TraceSourceLoggerTest.cs

Co-authored-by: Maryam Ariyan <maryam.ariyan@microsoft.com>