feat(test): report PrepareWorkingDirectoryError reason

Author: arxanas

git-branchless-lib/src/git/run.rs

@@ -42,6 +42,7 @@ impl std::fmt::Debug for GitRunInfo {
 }
 
 /// Options for invoking Git.
+#[derive(Clone)]
 pub struct GitRunOpts {
     /// If set, a non-zero exit code will be treated as an error.
     pub treat_git_failure_as_error: bool,

git-branchless-submit/src/phabricator.rs

@@ -446,7 +446,7 @@ Differential Revision: https://phabricator.example.com/D000$(git rev-list --coun
                     }
                 };
                 match test_output.test_status {
-                    TestStatus::CheckoutFailed
+                    TestStatus::CheckoutFailed(_)
                     | TestStatus::SpawnTestFailed(_)
                     | TestStatus::TerminatedBySignal
                     | TestStatus::AlreadyInProgress
@@ -708,7 +708,7 @@ Differential Revision: https://phabricator.example.com/D000$(git rev-list --coun
             .into_iter()
             .partition(|(_commit_oid, test_output)| match test_output.test_status {
                 TestStatus::Passed { .. } => true,
-                TestStatus::CheckoutFailed
+                TestStatus::CheckoutFailed(_)
                 | TestStatus::SpawnTestFailed(_)
                 | TestStatus::TerminatedBySignal
                 | TestStatus::AlreadyInProgress