Better error handling for git-merge-tree(1)
We're now extensively using git-merge-tree(1) for ListConflictFiles under the featureflag: gitaly_list_conflict_files_merge_tree
. However, there seems to be some issues around parsing the git-merge-tree(1)'s stderr, which holds the conflict information.
We can see that there are some cases of InternalErrors
From the logs, we cannot determine sufficiently why this is happening (albeit the number of cases being small). This MR introduces structerr to MergeTree
in order to provide more insight into the issue.
Part of: #5098 (closed)