[cairo] Builds failing on Gitlab CI

[Ayman El Didi]

> I noticed the CI keeps failing on the fedora autotools
> build step with the error:
> 
>    failed to pull image 
> "registry.freedesktop.org/aeldidi/cairo/fedora/34:2021-08-26.0" with 
> specified policies [always]: Error response from daemon: manifest for 
> registry.freedesktop.org/aeldidi/cairo/fedora/34:2021-08-26.0 not found 
> (manager.go:203:0s)

For anyone coming across this in the future, I fixed it by retrying the 
CI jobs.