OBS: fix python 3.12 compat

Fix for:

  File "/home/user/code/osmo-dev/src/osmo-ci/scripts/obs/lib/__init__.py", line 112, in check_required_programs
    if not importlib.find_loader(module):
           ^^^^^^^^^^^^^^^^^^^^^
AttributeError: module 'importlib' has no attribute 'find_loader

Change-Id: I6430c2c4f75c8408d00305e1a1f0a64600eb086c
---
M scripts/obs/lib/__init__.py
1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/scripts/obs/lib/__init__.py b/scripts/obs/lib/__init__.py
index 5292dc5..a85f777 100644
--- a/scripts/obs/lib/__init__.py
+++ b/scripts/obs/lib/__init__.py
@@ -1,7 +1,7 @@
 #!/usr/bin/env python3
 # SPDX-License-Identifier: GPL-2.0-or-later
 # Copyright 2022 sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
-import importlib
+import importlib.util
 import os
 import shutil
 import subprocess
@@ -95,7 +95,7 @@
             ok = False
 
     for module in lib.config.required_python_modules:
-        if not importlib.find_loader(module):
+        if not importlib.util.find_spec(module):
             print(f"ERROR: missing python3 module: {module}")
             ok = False
 

