fix: qrcode: make sure that imported qrcode package with QRCode

There are other packages with the same name...

kupfer/plugin/show_qrcode.py

@@ -11,17 +11,20 @@
 import io
 import tempfile
 from contextlib import closing
-import typing as ty
+from gettext import gettext as _
 
 import qrcode
+
 from gi.repository import GdkPixbuf, Gtk
 
 from kupfer import plugin_support
 from kupfer.obj import Action, FileLeaf, Leaf, TextLeaf
 from kupfer.ui import uiutils
 
-if ty.TYPE_CHECKING:
-    from gettext import gettext as _
+
+if not hasattr(qrcode, "QRCode"):
+    raise ImportError("missing (right) qrcode package")
+
 
 __kupfer_settings__ = plugin_support.PluginSettings(
     {