DOC: use anonymous hyperlinks for embedded URLs

Author: mgeier

NEWS.rst

@@ -148,7 +148,7 @@ Version 0.8.0 -- 2020-10-20 -- PyPI__ -- diff__
    To get rid of those ugly greenish code blocks,
    remove ``pygments_style = 'sphinx'`` from your ``conf.py``.
  * Switch documentation to
-   `insipid <https://insipid-sphinx-theme.readthedocs.io/>`_ theme by default
+   `insipid <https://insipid-sphinx-theme.readthedocs.io/>`__ theme by default
  * Require Python 3.6+
 
 __ https://pypi.org/project/nbsphinx/0.8.0/
@@ -166,7 +166,7 @@ Version 0.7.0 -- 2020-05-08 -- PyPI__ -- diff__
    ``height`` and ``class`` attributes are supported.
  * CSS: prompts protrude into left margin if ``nbsphinx_prompt_width`` is
    too small. If you want to hide the prompts, use
-   `custom CSS <https://nbsphinx.readthedocs.io/en/0.7.0/custom-css.html>`_.
+   `custom CSS <https://nbsphinx.readthedocs.io/en/0.7.0/custom-css.html>`__.
 
 __ https://pypi.org/project/nbsphinx/0.7.0/
 __ https://github.com/spatialaudio/nbsphinx/compare/0.6.1...0.7.0

doc/a-normal-rst-file.rst

@@ -47,14 +47,14 @@ __ subdir/a-notebook-in-a-subdir.ipynb
     __ subdir/a-notebook-in-a-subdir.ipynb
 
 Finally, you can use `Embedded URIs`_, like this
-`link <subdir/a-notebook-in-a-subdir.ipynb>`_.
+`link <subdir/a-notebook-in-a-subdir.ipynb>`__.
 
 .. _Embedded URIs: https://docutils.sourceforge.io/docs/ref/rst/
                    restructuredtext.html#embedded-uris-and-aliases
 
 .. code-block:: rst
 
-    like this `link <subdir/a-notebook-in-a-subdir.ipynb>`_.
+    like this `link <subdir/a-notebook-in-a-subdir.ipynb>`__.
 
 .. note::
 
@@ -80,7 +80,7 @@ Links to Notebooks, Ye Olde Way
 
 In addition to the way shown above, you can also create links to notebooks (and
 other Sphinx source files) with
-`:ref: <https://www.sphinx-doc.org/en/master/usage/referencing.html#role-ref>`_.
+`:ref: <https://www.sphinx-doc.org/en/master/usage/referencing.html#role-ref>`__.
 This has some disadvantages:
 
 * It is arguably a bit more clunky.
@@ -218,7 +218,7 @@ syntax, see the section about
 `citations in Markdown cells <markdown-cells.ipynb#Citations>`__.
 
 You can create a list of references in any reStructuredText file
-(or `reST cell <raw-cells.ipynb#reST>`_ in a notebook) like this:
+(or `reST cell <raw-cells.ipynb#reST>`__ in a notebook) like this:
 
 .. code-block:: rst
 
@@ -296,7 +296,7 @@ The following example gallery was created using:
 
 .. seealso::
 
-    `Link Galleries in Jupyter Notebooks <gallery/gallery-with-links.ipynb>`_
+    `Link Galleries in Jupyter Notebooks <gallery/gallery-with-links.ipynb>`__
 
 
 Thumbnail Galleries

doc/orphan.ipynb

@@ -26,7 +26,7 @@
     "* ... from a [reST page](a-normal-rst-file.rst#links-to-notebooks-and-other-sphinx-source-files) using\n",
     "\n",
     "    ```rst\n",
-    "    `some link text <notebookname.ipynb>`_\n",
+    "    `some link text <notebookname.ipynb>`__\n",
     "    ```\n",
     "\n",
     "Sphinx raises a warning in case of orphaned documents:\n",