Updates Tabulator package from 5.4 to 6.3
The relevant breaking change is the change of the `selectable` variable to `selectableRows`
Reviewed-on: https://projects.blender.org/studio/flamenco/pulls/104390
Reviewed-by: Sybren A. Stüvel <sybren@blender.org>
Try to get the `.editorconfig` and `.prettierrc` files as close as possible
to the formatting that was used in Flamenco. Because these files weren't
here during most of Flamenco's development so far, having them caused quite
a few changes in the webapp files.
No functional changes intended.
