Fix docstring markup in sage/matroids, sage/geometry, sage/modules #34167
Description
Part of #34157:
sage/matroids/graphic_matroid.py:325:1: RST214 Inline literal start-string without end-string.
sage/modules/tutorial_free_modules.py:3:1: RST303 Unknown directive type "MODULEAUTHOR".
sage/modules/tensor_operations.py:250:1: RST303 Unknown directive type "todo".
sage/modules/tensor_operations.py:327:1: RST215 Inline interpreted text or phrase reference start-string without end-string.
sage/modules/free_module.py:455:1: RST303 Unknown directive type "todo".
Not fixed here (comment:3, comment:4)
sage/geometry/polyhedron/constructor.py:174:1: RST201 Block quote ends without a blank line; unexpected unindent.
Depends on #30448
Depends on #22349
CC: @tscrim @jhpalmieri
Component: documentation
Author: Frédéric Chapoton, John Palmieri
Branch: f9c8724
Reviewer: Kwankyu Lee
Issue created by migration from https://trac.sagemath.org/ticket/34167