Revert out-of-scope changes

Author: pllim

CONTRIBUTING.rst

@@ -76,7 +76,7 @@ Code
     * Variable names should be descriptive, e.g., ``galaxy_mass``, ``u_mag``
 * Use the print function explicitly to display information about variables
 * As much as possible, comply with `PEP8 <https://www.python.org/dev/peps/pep-0008/>`_.
-* As much as possible, comply with Jupyter notebook style guides - `STScI style guide <https://github.com/spacetelescope/style-guides/blob/main/guides/jupyter-notebooks.md>`_ and `Official Coding Style <https://jupyter.readthedocs.io/en/latest/development_guide/coding_style.html>`_.
+* As much as possible, comply with Jupyter notebook style guides - `STScI style guide <https://github.com/spacetelescope/style-guides/blob/master/guides/jupyter-notebooks.md>`_ and `Official Coding Style <https://jupyter.readthedocs.io/en/latest/development_guide/coding_style.html>`_.
 * Imports
     * Do not use ``from package import *``; import packages, classes, and
       functions explicitly
@@ -244,7 +244,7 @@ procedure:
 
   If you do this, the only change necessary when merging your notebook will be to set ``tutorialpath`` to  ``'http://data.astropy.org/tutorials/My-tutorial-name/'``.
 
-For larger data files that are bigger than 10 MB in size, we recommend hosting with Zenodo. 
+For larger data files that are bigger than 10 MB in size, we recommend hosting with Zenodo.
 To use this approach, follow these steps:
 
 * You will need to sign up for an account with Zenodo before you can upload a file there.

scripts/convert.py

@@ -131,7 +131,7 @@ def convert(self, remove_executed=False):
             return self._rst_path
 
         # Initialize the resources dict - see:
-        # https://github.com/jupyter/nbconvert/blob/main/nbconvert/nbconvertapp.py#L327
+        # https://github.com/jupyter/nbconvert/blob/master/nbconvert/nbconvertapp.py#L327
         resources = {}
         resources['config_dir'] = '' # we don't need to specify config
         resources['unique_key'] = self.nb_name

tutorials/_static/bootstrap_sandstone.css

@@ -3,7 +3,7 @@
      id="dLabelGlobalToc"
      data-toggle="dropdown"
      data-target="#"
-     href="{{ pathto(main_doc) }}">{{ theme_navbar_site_name }} <b class="caret"></b></a>
+     href="{{ pathto(master_doc) }}">{{ theme_navbar_site_name }} <b class="caret"></b></a>
   <ul class="dropdown-menu globaltoc"
       role="menu"
       aria-labelledby="dLabelGlobalToc">{{ toctree(maxdepth=theme_globaltoc_depth|toint, collapse=False, includehidden=theme_globaltoc_includehidden|tobool) }}</ul>