progress bar unit tests: skip non-utf8

tests/progbar.cpp

@@ -7,6 +7,10 @@ TEST_CASE("ProgressBar") {
   if(!nc_){
     return;
   }
+  if(!notcurses_canutf8(nc_)){
+    CHECK(0 == notcurses_stop(nc_));
+    return;
+  }
   struct ncplane* n_ = notcurses_stdplane(nc_);
   REQUIRE(n_);
   REQUIRE(0 == ncplane_cursor_move_yx(n_, 0, 0));