Revert "gdbus-codegen: upgraded package to upstream"

This reverts commit b08a175a320e2207c9c9be876400337f57da56ca.

Reason for revert: This CL on main was reverted due to flakiness

Original change's description:
> gdbus-codegen: upgraded package to upstream
>
> Upgraded dev-util/gdbus-codegen to version 2.66.7 on x86
>
> I needed to add python3_6 compatibility for this to work.
>
> BUG=b:181107534
> TEST=cq
>
> Change-Id: I370a82f040b4079aa78507fd84b413606ccb7bc9
> Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/portage-stable/+/2719086
> Reviewed-by: Manoj Gupta <manojgupta@chromium.org>
> Commit-Queue: Robert Kolchmeyer <rkolchmeyer@google.com>
> Tested-by: Robert Kolchmeyer <rkolchmeyer@google.com>

Bug: b:181107534
Change-Id: I93e03d1220db46961f919c6913e79a2b36f050da
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/portage-stable/+/2723951
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Robert Kolchmeyer <rkolchmeyer@google.com>
Tested-by: Robert Kolchmeyer <rkolchmeyer@google.com>
3 files changed