@Ehsan I have a similar issue, running on Ubuntu 20.04.6 LTS, with Linux 5.15.0-46-generic and glibc 2.31. I am following the GPU intro tutorial.
I added the following to my pixi.toml:
[system-requirements]
linux = "5.15"
libc = { family = "glibc", version = "2.31" }
and ran pixi add modular, and then pixi run mojo --version.
I get the following errors when runningpixi run mojo --version :
/lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.32' not found 
/lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.33' not found
and other related glibc version issues. How can I resolve this? Upgrading glibc is not an option for me.