Original PR description

Up until the introduction of bootstrap in this repository, we have
had to make specific style rules inside Odoo for both versions of
spreadsheet to look the same. Concretely, we had to override
o-spreadsheet rules inside documents_spreadsheet because the former did
not have default css rules introduced by bootstrap (e.g.
vertical-align: middle on icons).

Now that bootstrap is part of o_spreadsheet, the old o-spreadsheet rules
have become obsolete and as we removed them, we did not correctly adapt
documents_spreadsheet. With bootstrap, we can however define rules
directly in the components definition as those will applied in both
o-spreadsheet and documents_spreadsheet.

Co-authored-by: Pierre Rousseau <pro@odoo.com>

Task 2531049