Update to Octave keyword list

[gedit_user]

Hello

Based on Update syntax highlighting rules for gedit, here is a patch for gtksourceview-4/language-specs/octave.lang to add a missing keyword uniquetol that was added to Octave in 2021:

1658a1659
>       <keyword>uniquetol</keyword>

[swilmet (Sébastien Wilmet)]

To contribute to GtkSourceView, it’s on GitLab, not here on Discourse (but you need to use git, and create a merge request).

But thanks