Before this commit, and in 13.0, you had access to gray colors in
bootstrap_overridden.scss files through the `palette-gray` function but
only if the gray was explicitely defined in the theme palette. This was
fine as only those were used at that time. Now, some themes want to use
the default BS gray values in those files to customize other variables.
The solution is to "force" all grays in the selected gray palette, using
the BS values by default.
closesodoo/odoo#50640
X-original-commit: fcb62edf3118d2d615296f293e6694b0e533bc99
Signed-off-by: Quentin Smetz (qsm) <qsm@odoo.com>