Remove redundant modifiers like public on interface members.

Remove redundant modifiers like static on interface.

Author: garydgregory

src/test/java/org/apache/commons/csv/PerformanceTest.java

@@ -241,8 +241,8 @@ private static void testParser(final String msg, final CSVParserFactory fac) thr
     }
 
     @FunctionalInterface
-    private static interface CSVParserFactory {
-        public CSVParser createParser() throws IOException;
+    private interface CSVParserFactory {
+        CSVParser createParser() throws IOException;
     }
 
     private static void testParseCommonsCSV() throws Exception {