Clean up a couple non-proposal docs links that had access issues. (#2565)

The toolchain link just needed a resourcekey.

The open discussion link may just not work because it was pre-go-public, so it points at a doc that we probably copied.

Co-authored-by: josh11b <josh11b@users.noreply.github.com>

docs/design/classes.md

@@ -1968,7 +1968,7 @@ There are some opportunities to improve on and simplify the C++ story:
     aren't friends of the base class.
 
 **References:** This was discussed in
-[the open discussion on 2021-07-12](https://docs.google.com/document/d/14vAcURDKeH6LZ_TQCMRGpNJrXSZCACQqDy29YH19XGo/edit#heading=h.40jlsrcgp8mr).
+[the open discussion on 2021-07-12](https://docs.google.com/document/d/1TvHK6HWAcCtnseMpcNsLYrgdtNy9qNrv6EaY9n063ok/edit#heading=h.40jlsrcgp8mr).
 
 #### Interop with C++ inheritance
 

toolchain/README.md

@@ -7,5 +7,5 @@ SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 -->
 
 A design is currently maintained in
-[Google Drive](https://docs.google.com/document/d/1RRYMm42osyqhI2LyjrjockYCutQ5dOf8Abu50kTrkX0/edit).
+[Google Drive](https://docs.google.com/document/d/1RRYMm42osyqhI2LyjrjockYCutQ5dOf8Abu50kTrkX0/edit?resourcekey=0-kHyqOESbOHmzZphUbtLrTw).
 It'll be migrated to markdown once we are confident in its stability.