fix issues reported by codacy

src/main/res/layout/activity_sso_grant_permission.xml

@@ -39,6 +39,7 @@
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         app:srcCompat="@drawable/background"
-        app:layout_constraintTop_toBottomOf="@id/tvInfoText"/>
+        app:layout_constraintTop_toBottomOf="@id/tvInfoText"
+        android:contentDescription="@string/single_sign_on_request_token_app_icon" />
 
 </android.support.constraint.ConstraintLayout>

src/main/res/values/strings.xml

@@ -819,4 +819,5 @@
     <string name="account_creation_failed">Account creation failed</string>
 
     <string name="single_sign_on_request_token" formatted="true">App %1$s wants access to your Nextcloud account (%2$s), do you want to grant permission?</string>
+    <string name="single_sign_on_request_token_app_icon" translatable="false">AppIcon</string>
 </resources>