Add metall v0.29

[liss-h]

Summary

Changes to recipe: metall/0.29

Motivation

Add new metall v0.29 release

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• Read the contributing guidelines
• Checked that this PR is not a duplicate: list of PRs by recipe
• Tested locally with at least one configuration using a recent version of Conan

[AbrilRBS]

Hi @liss-h, thanks a lot for taking the time to open the PR to keep the library up-to-date, we appreciate it :)

You'll need to add an entry into recipes/metall/config.yml for the new version too for this PR to be mergeable, otherwise the rest looks good!

[liss-h]

Hi, it seems like the CI builds with an old glibc version that does not meet the requirements of metall.

Not entirely sure what to do about this 😅, especially because I didn't change the requirement in the package and it worked previously (#23677)