Revert "Disable PolymerSecurityTokenPinTest.All on Debug runs"

This reverts commit 1a31008ebac4168354c7b082dc04bebe92fecc47.

Reason for revert: The test was failing before because of the long
loading time of OOBE. The issue was not with the test itself.

Timeouts have been increased and tests are now failing less often.

Bug: 1327650
Fixed: 1304295

Original change's description:
> Disable PolymerSecurityTokenPinTest.All on Debug runs
>
> These tests run quite slowly on debug builds causing regular flaky
> failures.
>
> Bug: 1304295
> Change-Id: Ia363ef44cade91a68af6ca1c4f0aa95ad1e8f6ff
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3561258
> Auto-Submit: Robert Flack <flackr@chromium.org>
> Reviewed-by: Michael Ershov <miersh@google.com>
> Commit-Queue: Robert Flack <flackr@chromium.org>
> Owners-Override: Robert Flack <flackr@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#987038}

Bug: 1304295
Change-Id: I997474a2bb1f00a2a33eeda036637e71d435b8f4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3657649
Reviewed-by: Danila Kuzmin <dkuzmin@google.com>
Commit-Queue: Renato Silva <rrsilva@google.com>
Cr-Commit-Position: refs/heads/main@{#1006358}