fix(ui5-view-settings-dialog): provide additional filters count description

[unazko]

Fixes: #11040

[nnaydenow]

No need to add it into template literal.

Now, when the item is accessed the screen reader is reading out selected filter criteria instead of item text + counter information.

In OpenUi5 the current when the filter item has selected items inside it it is reading the item's text, counter {number}.

I would suggest you to change this method to function instead of getter that accepts FilterItem and to extract the needed information as follows:

	_selectedFiltersLabel(item: FilterItem) {
		if (item.additionalText) {
			return ViewSettingsDialog.i18nBundle.getText(VSD_SELECTED_FILTER_COUNT, item.text || "", item.additionalText || "");
		}

		return item.text;
	}