Add news entry

vanschelven · vanschelven · commit c1d3b2786dd5 · 2021-02-23T11:58:37.000+01:00
diff --git a/news/9647.doc.rst b/news/9647.doc.rst
@@ -0,0 +1 @@
+Add warning about --extra-index-url and dependency confusion

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	`1`	`+Add warning about --extra-index-url and dependency confusion`