Remove auth popup since checkout has it's own login popup.

vovayatsyuk · vovayatsyuk · commit 8c0e20ca32d0 · 2021-08-18T18:04:55.000+03:00
Additionally this fixes duplicate ids ARIA errors
diff --git a/app/code/Magento/Customer/view/frontend/layout/checkout_index_index.xml b/app/code/Magento/Customer/view/frontend/layout/checkout_index_index.xml
@@ -0,0 +1,7 @@
+<?xml version="1.0"?>
+<page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+        xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_configuration.xsd">
+    <body>
+        <referenceBlock name="authentication-popup" remove="true"/>
+    </body>
+</page>
