set background color for password dialog

Signed-off-by: Marcel Hibbe <dev@mhibbe.de>

app/src/main/java/com/nextcloud/talk/conversationcreation/ConversationCreationActivity.kt

@@ -60,6 +60,7 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.platform.LocalView
+import androidx.compose.ui.res.colorResource
 import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.style.TextAlign
@@ -471,6 +472,8 @@ fun ShowPasswordDialog(onDismiss: () -> Unit, conversationCreationViewModel: Con
     var password by remember { mutableStateOf("") }
 
     AlertDialog(
+        containerColor = colorResource(id = R.color.dialog_background),
+
         onDismissRequest = onDismiss,
         confirmButton = {
             Button(onClick = {