[DL]String additions to 'gnome-builder.main'

This is an automatic notification from status generation scripts on:
https://l10n.gnome.org.

There have been following string additions to module 'gnome-builder.main':

+ "Enables the expirimental Proc Macros feature of rust-analyzer"
    + "Features"
    + "Proc Macros"

Note that this doesn't directly indicate a string freeze break, but it
might be worth investigating.
https://gitlab.gnome.org/GNOME/gnome-builder/commits/main