Revert "Roll Fuchsia SDK from 6.20211026.2.1 to 6.20211026.3.1"

This reverts commit d881c387381fb3323f0d420fdfc3fe6585a2b402.

Reason for revert: suspect of breaking deterministic builds.

Bug: 1263979

Original change's description:
> Roll Fuchsia SDK from 6.20211026.2.1 to 6.20211026.3.1
>
> If this roll has caused a breakage, revert this CL and stop the roller
> using the controls here:
> https://autoroll.skia.org/r/fuchsia-sdk-chromium-autoroll
> Please CC chrome-fuchsia-gardener@grotations.appspotmail.com on the revert to ensure that a human
> is aware of the problem.
>
> To file a bug in Chromium: https://bugs.chromium.org/p/chromium/issues/entry
>
> To report a problem with the AutoRoller itself, please file a bug:
> https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug
>
> Documentation for the AutoRoller is here:
> https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md
>
> Cq-Include-Trybots: luci.chromium.try:fuchsia-arm64-cast;luci.chromium.try:fuchsia-deterministic-dbg;luci.chromium.try:fuchsia-x64-cast
> Tbr: chrome-fuchsia-gardener@grotations.appspotmail.com
> Disable-Retries: true
> Change-Id: I38cce74e11e1be5cf583056f003930800599ba9e
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3246359
> Commit-Queue: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
> Bot-Commit: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
> Cr-Commit-Position: refs/heads/main@{#935293}

Change-Id: I06afcc3d990a79f2a67a93f8a1e362fd79e33070
Cq-Include-Trybots: luci.chromium.try:fuchsia-arm64-cast;luci.chromium.try:fuchsia-deterministic-dbg;luci.chromium.try:fuchsia-x64-cast
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3247197
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Owners-Override: Mikel Astiz <mastiz@google.com>
Commit-Queue: Mikel Astiz <mastiz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#935394}