Perform manual testing of gateway peer going down cleanly

[davidkel]

Issues raised

• https://github.com/hyperledger/fabric-gateway/issues/248 (appears to be fixed)
• https://github.com/hyperledger/fabric-gateway/issues/262 (appears to be fixed)
• https://github.com/hyperledger/fabric-gateway/issues/261 (documentation issue)

blocked by github.com/hyperledger/fabric#2985

[davidkel]

Now unblocked, and testing has been done with the following new issues raised

• https://github.com/hyperledger/fabric-gateway/issues/265 (retested and is fixed)
• https://github.com/hyperledger/fabric-gateway/issues/269 (mainly doc but might need to split off the enhancement)

[davidkel]

This just uses the StopAndRestartGateway scenario