### Please describe the problem.

I have syncing set up between two peers via tor.  Sometimes when I change a (non-annexed) file in one peer, the other peer receives the change, but then within a second or two adds a commit which removes the entire file, and within another second another commit which adds it back.

### What steps will reproduce the problem?

This is not 100% reproducible.  I haven't figured out any pattern yet as to when it happens or doesn't happen.

1. Set up a fresh repo
1. `echo '* annex.largefiles=nothing' >.gitattributes` and commit
1. Add another (text) file and commit
1. `scp` the repo to another machine
1. Run `enable-tor`, `remotedaemon`, and `p2p --pair` on both
1. Modify the text file
1. Observe that the remote peer ends up with three new commits on `master` rather than one; from oldest to newest:
    1. The commit received via tor from the source side (4bd9c99 in the below example)
    2. A local commit removing the text file (1ef9061)
    3. A local commit adding it back with identical contents (e662a33)

### What version of git-annex are you using? On what operating system?

7.20190912-g05bc37910 on both openSUSE nodes (sender is Leap 15.0, receiver is Tumbleweed)

### Please provide any additional information below.

[[!format sh """
# Relevant output from .git/annex/daemon.log on the sending side
[2019-09-29 23:44:13.781640446] Committer: Committing changes to git
(recording state in git...)
[2019-09-29 23:44:15.105628185] Committer: Committing changes to git

Updating 4bd9c99..1ef9061
Fast-forward
 TODO.org | 10919 --------------------------------------------------------------------------------------------------------------------------------------------
 1 file changed, 10919 deletions(-)
 delete mode 100644 TODO.org
[2019-09-29 23:44:17.668876311] Committer: Committing changes to git
(recording state in git...)

Updating 1ef9061..e662a33
Fast-forward
 TODO.org | 10919 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 10919 insertions(+)
 create mode 100644 TODO.org


# Relevant output from .git/annex/daemon.log on the receiving side
[2019-09-29 23:44:14.293079441] RemoteControl: Syncing with peer1 
From tor-annex::rpxkm55i6gxlirqohcjup4g4orlgzyval2n2yymah36ekipjcppmrvid.onion:42294
   28aa4b9..4bd9c99  master        -> peer1/master
   28aa4b9..4bd9c99  synced/master -> peer1/synced/master

Updating 28aa4b9..4bd9c99
Fast-forward
 TODO.org | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
[2019-09-29 23:44:16.054093704] Committer: Committing changes to git
(recording state in git...)
[2019-09-29 23:44:16.169742975] Pusher: Syncing with peer1 
[2019-09-29 23:44:17.169984217] Committer: Committing changes to git
(recording state in git...)
To tor-annex::rpxkm55i6gxlirqohcjup4g4orlgzyval2n2yymah36ekipjcppmrvid.onion:42294
   4bd9c99..1ef9061  master -> synced/master
remote: error: refusing to update checked out branch: refs/heads/master        
To tor-annex::rpxkm55i6gxlirqohcjup4g4orlgzyval2n2yymah36ekipjcppmrvid.onion:42294
 ! [remote rejected] master -> master (branch is currently checked out)
error: failed to push some refs to 'tor-annex::rpxkm55i6gxlirqohcjup4g4orlgzyval2n2yymah36ekipjcppmrvid.onion:42294'
[2019-09-29 23:44:23.623525612] Pusher: Syncing with peer1 
To tor-annex::rpxkm55i6gxlirqohcjup4g4orlgzyval2n2yymah36ekipjcppmrvid.onion:42294
   1ef9061..e662a33  master -> synced/master

# End of transcript or log.
"""]]
