please let's disable the ECC plugin in CI, in its current form

["Laszlo Ersek" <lersek@redhat.com>]

Hi All,

in my opinion, the ECC plugin in CI has not been productive or helpful.
The errors it reports are not convincing, and exceptions are difficult
to add, or even express. I request that we disable ECC globally for
edk2, or at least make it controllable through a github PR flag (not
through CI metafile changes in edk2).

(Metafile changes could be an acceptable way of controlling ECC if (a)
they didn't have to go through review, (b) if technically such changes
would take effect in CI even if they were included in the patch series
subject to the CI run. Then a maintainer could evaluate and
*immediately* suppress such ECC issues by adding the exceptions as a
prepended patch, and force-pushing the updated branch to the same open
PR. But this would remain much inferior to simply disabling ECC, or
controlling it through a PR label.)

Thanks
Laszlo