kdepim-addons: Fix for the digital clock changing calendar colors

[Akseli Lahtinen]

Hi!

kdepim-addons has had a bug for a while in various distros where enabling showing 
calendar events in digital clock causes calendar colors to change every time it is opened.

There has been a fix for it that should be rather easy to backport, 
if your users are encountering this bug.

https://invent.kde.org/pim/kdepim-addons/-/commit/b5f70b11b8f618d639598c5d04e264ab1463d321

I am not kde-pim developer myself, just an user of this addon. 
When testing this recently it fixed the issue for me.

Just wanted to let you know!

Best regards,
- Akseli