message: Replace use of `string_format` in TileInspector
  Maybe slightly less readable, but `string_format` is likely to be
  removed at some point, at least in its current form.
diff: @@ -74,7 +74,7 @@ void TileInspector::update()
  }
  position = rect().startPoint() + NAS2D::Vector{5, 62};
  - drawTitleText(position, "Location: ", string_format("%i, %i", mTile->x(), mTile->y()));
  + drawTitleText(position, "Location: ", std::to_string(mTile->x()) + ", " + std::to_string(mTile->y()));
  position.y() += 10;
  drawTitleText(position, "Terrain: ", TILE_INDEX_TRANSLATION[mTile->index()]);
  