Open Editors: unable to open file in a specific group if opened in other group and setting workbench.editor.revealIfOpen

[bpasero]

Steps to Reproduce:

1. open the same file in 2 groups
2. configure workbench.editor.revealIfOpen: true
3. try to click on the file in the one group and in the other

=> 🐛 it is not possible to open each, only one

//cc @isidorn

[isidorn]

@bpasero thanks for fixing this.