It seems that there might be an issue (perhaps with encoding?) on the build server. All of the tests passed on my machine before pushing up, and going through the logs, to the naked eye it seems that the test (test_lowercase_05) should have passed:

java.lang.Exception: Comparison failed.
Expected <e_lowercase5><one>`Ÿ A 8 O İ</one><lower>`ÿ a 8 o i̇</lower></e_lowercase5>
Actual <e_lowercase5><one>`Ÿ A 8 O İ</one><lower>`ÿ a 8 o i</lower></e_lowercase5>
Differences were (path, expected, actual): (e_lowercase5/lower,'`ÿ a 8 o i̇','`ÿ a 8 o i')

I have moved the test from scala to scala-debug for now.

daffodil-test/src/test/scala-debug/edu/illinois/ncsa/daffodil/section23/dfdl_expressions/TestDFDLExpressionsDebug.scala
daffodil-test/src/test/scala/edu/illinois/ncsa/daffodil/section23/dfdl_expressions/TestDFDLExpressions.scala
daffodil-test/src/test/resources/edu/illinois/ncsa/daffodil/section23/dfdl_functions/Functions.tdml