[fix] little typo

_sources/dev/translation.txt

 
 You may have errors here. In that case, edit the
 ``update-translations.sh`` script to change ``pybabel`` to
-``pybabel-python2 or pybabel2``
+``pybabel-python2`` or ``pybabel2``
 
 After this step, you can modify the .po files.
 

dev/translation.html

 </div>
 <p>You may have errors here. In that case, edit the
 <code class="docutils literal"><span class="pre">update-translations.sh</span></code> script to change <code class="docutils literal"><span class="pre">pybabel</span></code> to
-<code class="docutils literal"><span class="pre">pybabel-python2</span> <span class="pre">or</span> <span class="pre">pybabel2</span></code></p>
+<code class="docutils literal"><span class="pre">pybabel-python2</span></code> or <code class="docutils literal"><span class="pre">pybabel2</span></code></p>
 <p>After this step, you can modify the .po files.</p>
 </div>
 <div class="section" id="compile-translations">

docs/dev/translation.rst

 
 You may have errors here. In that case, edit the
 ``update-translations.sh`` script to change ``pybabel`` to
-``pybabel-python2 or pybabel2``
+``pybabel-python2`` or ``pybabel2``
 
 After this step, you can modify the .po files.