Tracking branch is not updated on 'R'/refresh

[hoxu]

Steps to reproduce:

git init --bare remote.git
git clone remote.git tig
cd tig
git commit --allow-empty -m 'Initial commit'
git push -u
git checkout -b feature
git commit --allow-empty -m 'Feature'
git push -u origin feature
# start "tig status" in another terminal
git checkout master
# Press 'R' in tig, you see: "On branch master. Your branch is behind 'origin/feature' by 1 commit."

In other words, tig shows status for wrong tracking branch if the branch is changed from another terminal.

$ tig --version
tig version 2.5.1
ncurses version 5.7.20081102
readline version 8.0