aws-sdk-cpp transitively vendors s2n-tls. The current version of aws-sdk-cpp (1.11.471) relies on s2n-tls ~1.5.9. Given that we would like to directly vendor s2n-tls 1.7.3, it is necessary to first bump aws-sdk-cpp to a newer version that relies on s2n-tls 1.7.3 so that we don't end up with multiple s2n-tls versions vendored into the server.

aws-sdk-cpp 1.11.806 is the first release that relies on s2n-tls 1.7.3, so it best fits our need here.