micropython-lib: update to 1.28.0, add test.sh

micropython-lib is a companion repository to micropython, versioned in
lockstep. Both are now at 1.28.0 (released 2026-04-06).

The 001-build-unix-ffi.patch remains needed as the upstream has not yet
incorporated the --unix-ffi argument into the tools/build.py script.

test.sh:
- micropython-lib: verify stdlib-replacement modules (collections,
  functools, base64) can be imported via the /usr/lib/micropython path
- micropython-lib-unix: verify the micropython-unix wrapper script exists
  and that sqlite3/select are importable via the unix-ffi path

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

lang/python/micropython-lib/test.sh

@@ -0,0 +1,26 @@
+#!/bin/sh
+
+case "$1" in
+micropython-lib)
+	micropython -c "
+import sys
+sys.path.append('/usr/lib/micropython')
+import collections
+import functools
+import base64
+print('micropython-lib modules OK')
+"
+	;;
+micropython-lib-unix)
+	[ -x /usr/bin/micropython-unix ]
+	micropython-unix -c "
+import sys
+import sqlite3
+import select
+print('micropython-lib-unix modules OK')
+"
+	;;
+*)
+	exit 0
+	;;
+esac