Support website linking to old Slack

The following page is still linking to the old Slack: https://marketplace-support.jetbrains.com/hc/en-us

Hello @michael.gajda,

I’m sorry for the delay in our response! I thought it would take less time to update the links. But please be aware we are in the process of updating them. Thanks a lot for bringing this to our attention!

All the links are updated! Thanks again for bringing this to our attention :blush: