python-setuptools-rust: bump to 1.12.1

Changelog: https://github.com/PyO3/setuptools-rust/releases/tag/v1.12.1

Patch release. Add test.sh to verify RustExtension import.

Signed-off-by: Alexandru Ardelean <alex@shruggie.ro>

lang/python/python-setuptools-rust/test.sh

@@ -0,0 +1,9 @@
+#!/bin/sh
+[ "$1" = python3-setuptools-rust ] || exit 0
+python3 - << 'EOF'
+import setuptools_rust
+assert setuptools_rust.__version__, "setuptools_rust version is empty"
+from setuptools_rust import RustExtension, RustBin, Binding
+ext = RustExtension("mymod", binding=Binding.PyO3)
+assert ext.name == "mymod"
+EOF