chromeos-base/protofiles: add python 3.8 compat entry

BUG=b/257113269
TEST=presubmit
RELEASE_NOTE=None

Change-Id: I6bdc9b662d18e2d620e0bae6ab2c71d16f0128eb
Reviewed-on: https://cos-review.googlesource.com/c/third_party/overlays/chromiumos-overlay/+/42250
Reviewed-by: Robert Kolchmeyer <rkolchmeyer@google.com>
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
1 file changed