[JDK 11] RFR 8198821: fix test methods access for test java/text/Normalizer/NormalizerAPITest.java

[Chris Yin]

Please review the minor change for test java/text/Normalizer/NormalizerAPITest.java, thanks

Added public access modifier to all “Test_" methods so they can be recognized as test method correctly by util class

bug: https://bugs.openjdk.java.net/browse/JDK-8198821 <https://bugs.openjdk.java.net/browse/JDK-8198821>
webrev: http://cr.openjdk.java.net/~xiaofeya/8198821/webrev.00/ <http://cr.openjdk.java.net/~xiaofeya/8198821/webrev.00/>

Regards,
Chris