There's a merged pull request on the void-packages repository

flintlib: update to 2.8.5.
https://github.com/void-linux/void-packages/pull/36945

Description:
Also, enable openblas (used for matrix multiplication)

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#### Testing the changes
- I tested the changes in this PR: **YES**

I ran sagemath long doctest suite with this. The update by itself is just a bugfix release, but I also took the chance to enable openblas for matrix multiplication so I wanted to make sure I didn't mess up (I had it disabled b/c of a misunderstanding on my part, it seems convenient to have it enabled.)

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