[FIX] *: RST cleanup

RST cleanup to comply with the RST guidelines. This is required so we
can use "make test", as there are currently hundreds of errors. For now,
it is unusable because of the oldest code in this repo.

closes odoo/documentation#3589

X-original-commit: 7ae76bad42
Signed-off-by: Castillo Jonathan (jcs) <jcs@odoo.com>

content/developer/reference/backend/data.rst

@@ -77,7 +77,7 @@ following attributes:
     Requires an :term:`external id`, defaults to ``True``.
 
 ``field``
-----------
+---------
 
 Each record can be composed of ``field`` tags, defining values to set when
 creating the record. A ``record`` with no ``field`` will use all default