SCRIPTS: publish-release: update the umask to keep group write access

This is to avoid the occasional error that arises when a release is
first done by another maintainer.
diff --git a/scripts/publish-release b/scripts/publish-release
index 3cf32d8..9066d4a 100755
--- a/scripts/publish-release
+++ b/scripts/publish-release
@@ -22,6 +22,9 @@
 DIR=
 DOC=( )
 
+# need to have group write on emitted files for others to update
+umask 002
+
 die() {
 	[ "$#" -eq 0 ] || echo "$*" >&2
 	exit 1