devel/samurai: Update to 1.2-16-gca5a6ba

This makes --version return 1.9.0 instead of 1.9. qt5-webengine's
configure checks for system ninja and tries to parse --version and
expects it to have 3 components. Without this qt5-webengine falls
back to using a bundled copy of ninja instead.

https://github.com/michaelforney/samurai/issues/70

PR: 254678