Tab renaming in :gui module, branch feature/web-gui

[fmuratori]

The following behaviour is implemented in the branch feature/web-gui in the module :gui

Following the renaming of a Page object, ApplicationImpl automatically generates an Event containing fields such as the old and new name respectively.

Bug:
In the implementation of ApplicationImpl, the resulting observable event provides the old name inside of the new name field.

More specifically, the implementation of file gui/src/commonMain/kotlin/it/unibo/tuprolog/ui/gui/impl/ApplicationImpl.kt at line 53 is:

page.onRename += { handlePageRenaming(it.event.first, it.event.first) }

Fix:

A possible fix to the implementation is shown below:

page.onRename += { handlePageRenaming(it.event.first, it.event.second) }