patch 8.0.1012: MS-Windows: problem with $HOME when is was set internally

Problem:    MS-Windows: Problem with $HOME when is was set internally.
Solution:   Only use the $HOME default internally. (Yasuhiro Matsumoto, closes
            #2013)
diff --git a/src/testdir/Make_all.mak b/src/testdir/Make_all.mak
index 678fc80..2a267d6 100644
--- a/src/testdir/Make_all.mak
+++ b/src/testdir/Make_all.mak
@@ -205,7 +205,8 @@
 	    test_writefile.res \
 	    test_alot_latin.res \
 	    test_alot_utf8.res \
-	    test_alot.res
+	    test_alot.res \
+	    test_windows_home.res
 
 
 # Explicit dependencies.