shill: vpn: Add vpn user to tun group

To make a VPN client able to clone /dev/net/tun to create a tunnel
interface.

BUG=b:177984585
BUG=b:177876632
TEST=Verified that a binary running as vpn:vpn can create tunnel
  interface.

Cq-Depend: chromium:2717252
Change-Id: I714f2addb61f8ad46f868622a7de45dea3f6ff8c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/eclass-overlay/+/2705371
Reviewed-by: Jorge Lucangeli Obes <jorgelo@chromium.org>
Reviewed-by: Taoyu Li <taoyl@chromium.org>
Tested-by: Jie Jiang <jiejiang@chromium.org>
Commit-Queue: Jie Jiang <jiejiang@chromium.org>
1 file changed
tree: d9b55d0e6c613966510e2d9c8d44dd4b336788bc
  1. OWNERS
  2. PRESUBMIT.cfg
  3. acct-group/
  4. acct-user/
  5. eclass/
  6. metadata/
  7. profiles/