Update Python version and GitHub actions versions

Author: pgleeson

.github/workflows/omv-ci.yml

@@ -14,7 +14,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: [ 3.9 ]
+        python-version: [ "3.12" ]
         engine: 
             - jNeuroML
             - jNeuroML_NEURON
@@ -28,10 +28,10 @@ jobs:
             - "PyNEURON:7.8.2"
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
 
     - name: Set up Python  ${{ matrix.python-version }}
-      uses: actions/setup-python@v3
+      uses: actions/setup-python@v4
       with:
         python-version:  ${{ matrix.python-version }}
 
@@ -40,8 +40,6 @@ jobs:
         pip install git+https://github.com/OpenSourceBrain/osb-model-validation
         pip install scipy sympy matplotlib cython pandas tables
                 
-        pip install 'numpy<=1.23.0' # see https://github.com/OpenSourceBrain/osb-model-validation/issues/91
-
         
     - name: Run OMV tests on engine ${{ matrix.engine }}
       run: |