Merge pull request pytorch#548 from seemethere/python39_notes

quick-start: Add a note about Python 3.9 installation

Author: seemethere

_includes/quick_start_local.html

@@ -33,7 +33,7 @@
         <div class="option-text">PyTorch Build</div>
       </div>
       <div class="col-md-6 option block version selected" id="stable">
-        <div class="option-text">Stable (1.7.0)</div>
+        <div class="option-text">Stable (1.7.1)</div>
       </div>
       <div class="col-md-6 option block version" id="preview">
         <div class="option-text">Preview (Nightly)</div>