tests: fixture 파일명과 unit 동기화

fec/tests/own/bad_clos.fe

@@ -1,13 +0,0 @@
-unit bad_clos;
-
-struct FileLike {
-    handle: i32,
-    fn close(self: Self) -> !void { self.handle = 0; }
-    fn drop(self: &mut Self) { self.handle = 0; }
-}
-
-fn bad() -> !void {
-    let file: FileLike = FileLike{ handle: 7 };
-    try file.close();
-    file.close();
-}