Build against lower Glibc for Ubuntu

[voylin]

There have been issues of people not being able to use the GDExtension due to the GDExtension being build against Glibc 2.38 whilst Ubuntu only has 2.35.

This can be solved by downgrading glibc before compiling, so something which needs to be added in the workflow and maybe with an argument adjusted, comment with a link to view what the most installed stable version is at the moment of compiling.