tictactoe: added test case to check not yed finished game

src/test/java/de/tims/tictactoe/GameLogicTest.java

@@ -238,7 +238,11 @@ class GameLogicTest {
 		    			Arguments.of("check tied game", true, new char[][] 
 															 {{'x', 'x', 'o'}, 
 															  {'o', 'x', 'o'},
-															  {'x', 'o', 'x'}})
+															  {'x', 'o', 'x'}}),
+		    			Arguments.of("check not yet finished game", false, new char[][] 
+																		 {{'x', 'x', '-'}, 
+																		  {'o', 'o', '-'},
+																		  {'x', 'o', 'x'}})
 		    		);
 	 }