Before we start, you must go to the chapter5 directory, where we made the original clone
for this chapter.

We should start by tagging the commit that is ten commits behind origin/stable-2.3 and is not a merge. In order to find that commit, we will use the git log command.

For the git log command, we are using the --no-merges option, which will show commits that only have one parent. The --oneline option we have used before tells Git to limit the output to one line per commit. Moreover, -11 shows us the last 11 commits (10 commits before the latest).

Find the commit as follows:

$ git checkout stable-2.3 
$ git log -11 --no-merges --oneline
49ec6c1 Prepare 2.3.2-SNAPSHOT builds
63dcece JGit v2.3.1.201302201838-r
3b41fcb Accept Change-Id even if footer contains not well-formed entries
5d7b722 Fix false positives in hashing used by PathFilterGroup
9a5f4b4 Prepare post 2.3.0.201302130906 builds
19d6cad JGit v2.3.0.201302130906
3f8ac55 Replace explicit version by property where possible
1c4ee41 Add better documentation to DirCacheCheckout
e9cf705 Prepare post 2.3rc1 builds
ea060dd JGit v2.3.0.201302060400-rc1
60d538f Add getConflictingNames to RefDatabase