Revert "Fix working_dir negative test error expectation (#1348)"

This reverts commit 2028de8.

During local testing a gcs with an older version of security policy
was used when doing the fix: #1322. As we can see, the quotations
weren't there. However, later a PR was merged, which added them: #1311

Signed-off-by: Maksim An <maksiman@microsoft.com>

test/cri-containerd/policy_test.go

@@ -382,7 +382,7 @@ func Test_RunContainer_InvalidContainerConfigs_NotAllowed(t *testing.T) {
  req.Config.WorkingDir = "/non/existent"
  return nil
  },
- expectedError: "working_dir /non/existent unmatched by policy rule",
+ expectedError: "working_dir \"/non/existent\" unmatched by policy rule",
  },
  {
  name: "InvalidCommand",