bpo-28334: netrc() now uses expanduser() to find .netrc file (GH-4537)

Previously, netrc.netrc() was raised an exception if $HOME is not set.

Authored-By: Dimitri Merejkowsky <dimitri.merejkowsky@tanker.io>
diff --git a/Misc/ACKS b/Misc/ACKS
index 0511390..fc7154f 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -1031,6 +1031,7 @@
 Lucas Prado Melo
 Ezio Melotti
 Doug Mennella
+Dimitri Merejkowsky
 Brian Merrell
 Alexis Métaireau
 Luke Mewburn