internal/history: document Go 1.17.6 and Go 1.16.13
internal/history: document Go 1.17.6 and Go 1.16.13

Change-Id: Ib96dbc7a4cf70c0c4e3548baef3a77bfc28fb55f
Reviewed-on: https://go-review.googlesource.com/c/website/+/375974
Run-TryBot: Carlos Amedee <ab5e2bca84933118bbc9d48ffaccce3bac4eeb64@golang.org>
TryBot-Result: Gopher Robot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Than McIntosh <4b2922593166fc595a9b1a408f34f5d3817fe9d2@google.com>
Trust: Carlos Amedee <29c458bbff2be5643384eb5215911934e5a9738f@google.com>
Run-TryBot: Carlos Amedee <29c458bbff2be5643384eb5215911934e5a9738f@google.com>

golang/website,golang/website,golang/website,golang/website,golang/website,golang/website,golang/website