dashboard: re-enable repos that exec 'go' on aix
dashboard: re-enable repos that exec 'go' on aix

The PATH issue that prompted us to skip these repos appears to be
fixed as of CL 354754.

The x/review repo had also been failing, apparently due to the same
PATH issue, and is now passing:
https://build.golang.org/log/5d976685f5d214a02a754b4327387f9fa101f256

Fixes golang/go#31567

Change-Id: I5c92688768823e503c757d2282ad012c7dc57519
Reviewed-on: https://go-review.googlesource.com/c/build/+/354755
Trust: Bryan C. Mills <1c8aad60184261ccede67f5c63a0d2a3bf3c9ff4@google.com>
Run-TryBot: Bryan C. Mills <1c8aad60184261ccede67f5c63a0d2a3bf3c9ff4@google.com>
TryBot-Result: Go Bot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Dmitri Shuralyov <d181b7fea0ec87c86ba5a890ab716db52498e3ba@golang.org>

golang/build,golang/build,golang/build,golang/build