.travis.yml: Upgrade the Ubuntu arm32 to 22.04 (Jammy).
Upgrade the gcc version to the latest version 11.4.0 to align the gcc version used in the RubyCI arm64 server.
.travis.yml: Upgrade the Ubuntu arm32 to 22.04 (Jammy).
Upgrade the gcc version to the latest version 11.4.0 to align the gcc
version used in the RubyCI arm64 server.