Update to new versions of Github CI actions

- actions/checkout@v3 --> v4
- matlab-actions/setup-matlab@v1 --> v2
- MATPOWER/action-configure-matlab@v1 --> v2

.github/workflows/continuous-integration.yml

@@ -23,7 +23,7 @@ jobs:
 
  steps:
  - name: Check out repository
- uses: actions/checkout@v3
+ uses: actions/checkout@v4
 
  - name: Install Octave (Linux)
  if: matrix.platform == 'octave' && startsWith(matrix.os, 'ubuntu')
@@ -35,11 +35,11 @@ jobs:
 
  - name: Install MATLAB
  if: matrix.platform == 'matlab'
- uses: matlab-actions/setup-matlab@v1
+ uses: matlab-actions/setup-matlab@v2
 
  - name: Configure MATLAB
  if: matrix.platform == 'matlab'
- uses: MATPOWER/action-configure-matlab@v1
+ uses: MATPOWER/action-configure-matlab@v2
 
  - name: ${{ env.ML_NAME }} ${{ env.ML_VER }} Installed
  run: $ML_CMD ver