Remove Saucelabs references from docs (#8800)

Test runs were disabled 2020-11: #8228
Code support was removed 2023-04: #8577

Author: alxndrsn

docs/_layouts/default.html

@@ -163,19 +163,6 @@ <h4>{{ page.sub_title}}</h4>
               >
             </a>
           </div>
-          <div class="col-xs-4 col-md-2">
-            <a
-              href="https://saucelabs.com"
-              target="_blank"
-              rel="noopener noreferrer"
-            >
-              <img
-                class="icon"
-                src="{{ site.baseurl}}/static/img/friends/saucelabs.svg"
-                alt="Saucelabs"
-              />
-            </a>
-          </div>
 
         </div>
 

docs/manifest.appcache

@@ -46,7 +46,6 @@ https://fonts.gstatic.com/s/opensans/v10/k3k702ZOKiLJc3WVjuplzBampu5_7CjHW5spxoe
 /static/img/friends/couchdb.svg
 /static/img/friends/github.svg
 /static/img/friends/leveldb.svg
-/static/img/friends/saucelabs.svg
 /static/img/friends/travis.svg
 /static/img/friends/twitter.svg