patch 8.0.0478: tests use assert_true(0) and assert_false(1) to report errors

Problem:    Tests use assert_true(0) and assert_false(1) to report errors.
Solution:   Use assert_report().
diff --git a/src/testdir/test_cursor_func.vim b/src/testdir/test_cursor_func.vim
index 3553541..d784e36 100644
--- a/src/testdir/test_cursor_func.vim
+++ b/src/testdir/test_cursor_func.vim
@@ -1,13 +1,7 @@
 " Tests for cursor().
 
 func Test_wrong_arguments()
-  try
-    call cursor(1. 3)
-    " not reached
-    call assert_false(1)
-  catch
-    call assert_exception('E474:')
-  endtry
+  call assert_fails('call cursor(1. 3)', 'E474:')
 endfunc
 
 func Test_move_cursor()