Packit: Create missing path components in files_to_sync

Packit's propose-downstream failed[0] for crun 1.17 because packit wasn't
able to create `tests/tmt` path structure in the downstream repo[1].
[0]: #1558
[1]: https://dashboard.packit.dev/jobs/propose-downstream/10800

Using `mkpath: true` will create missing path components if any.
Ref: https://packit.dev/docs/configuration#files_to_sync

Fixes: #1558

Signed-off-by: Lokesh Mandvekar <lsm5@fedoraproject.org>

.packit.yaml

@@ -11,12 +11,15 @@ files_to_sync:
  - src: plans/
  dest: plans/
  delete: true
+ mkpath: true
  - src: tests/tmt/
  dest: tests/tmt/
  delete: true
+ mkpath: true
  - src: .fmf/
  dest: .fmf/
  delete: true
+ mkpath: true
  - .packit.yaml
 
 packages: