qmlls not restarted when kit switches

Steps to reproduce:

• have two different Qt versions, one with qmlls correctly installed, one without
• depending on the Qt versions enable to allow qmlls even below Qt6.8
• do not check the use qmlls from latest Qt version
• set up / open a project with qml, use the kit with a non-working qmlls
• go to Projects view and switch to the kit using the Qt version holding a working qmlls
• check back on the qml file

if it is one of the "open documents" while switching the kit, the qmlls won't get updated/restarted to use the correct one

if you close it and re-open it, the correct qmlls will be used