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

bc-gh: update to 5.1.1
https://github.com/void-linux/void-packages/pull/33323

Description:
I am the author of the upstream software. The new `configure` arguments make this `bc` have the same behavior as GNU in a couple things.

Signed-off-by: Gavin Howard <gavin@yzena.com>

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#### General
- [ ] This is a new package and it conforms to the [quality requirements](https://github.com/void-linux/void-packages/blob/master/Manual.md#quality-requirements)

#### Have the results of the proposed changes been tested?
- [ ] I use the packages affected by the proposed changes on a regular basis and confirm this PR works for me
- [x] I generally don't use the affected packages but briefly tested this PR

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