migrate from PyQt6 to PySide6, remove unneeded dependencies

src/ui/widgets/admin_create_user.py

@@ -1,11 +1,11 @@
-from PyQt6 import QtWidgets
-from PyQt6.QtCore import pyqtSignal
+from PySide6 import QtWidgets
+from PySide6.QtCore import Signal
 from .widget_sources.admin_create_user_ui import Ui_Dialog
 from src.backend import AdminCommands, Database
 
 
 class UserCreate(QtWidgets.QDialog, Ui_Dialog):
-    admin_action_changed = pyqtSignal()
+    admin_action_changed = Signal()
 
     def __init__(self):
         super(UserCreate, self).__init__()