[python-control-developers] [python-control/python-control] f3e503: Update doc/index.rst unit test reference

[Ben G. <no...@gi...>]

  Branch: refs/heads/master
  Home:   https://github.com/python-control/python-control
  Commit: f3e503591367f216d265fd0dd9337693923ef72d
      https://github.com/python-control/python-control/commit/f3e503591367f216d265fd0dd9337693923ef72d
  Author: Ben Greiner <co...@bn...>
  Date:   2020-08-18 (Tue, 18 Aug 2020)

  Changed paths:
    M doc/index.rst

  Log Message:
  -----------
  Update doc/index.rst unit test reference

Sync doc dir test reference from #436. Same wording as in toplevel README.rst