Fix sonar-analysis job: Install Python 3.11 instead of 3.10

ISSUE:
======
- Ubuntu 22.04 comes with Python 3.10
- Project requires Python >=3.11 (pyproject.toml)
- Error: Package 'pote' requires a different Python: 3.10.12 not in '>=3.11'

FIX:
====
- Install Python 3.11 from deadsnakes PPA
- Install pip for Python 3.11
- Use python3.11 -m pip explicitly for all pip operations
- Use python3.11 -m pytest for test execution

CHANGES:
========
- Install software-properties-common for add-apt-repository
- Add deadsnakes PPA for Python 3.11
- Install python3.11, python3.11-dev, python3.11-venv, python3.11-distutils
- Install pip via get-pip.py for Python 3.11
- Update all pip/pytest commands to use python3.11 -m

This ensures the sonar-analysis job uses Python 3.11 as required.

.github/workflows/ci.yml

@@ -344,16 +344,27 @@ jobs:
             echo "⚠️ Warning: Could not verify SonarQube server connectivity (continuing anyway)"
           fi
 
-      - name: Install Python and dependencies
+      - name: Install Python 3.11 and dependencies
         run: |
-          apt-get update && apt-get install -y python3 python3-pip
+          apt-get update
-          pip3 install --upgrade pip
+          apt-get install -y software-properties-common
+          add-apt-repository -y ppa:deadsnakes/ppa
+          apt-get update
+          apt-get install -y python3.11 python3.11-dev python3.11-venv python3.11-distutils
+          # Install pip for Python 3.11
+          curl -sS https://bootstrap.pypa.io/get-pip.py | python3.11
+          # Ensure python3 and pip3 point to 3.11
+          update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.11 1 || true
+          # Use python3.11 -m pip for pip operations
+          python3.11 -m pip install --upgrade pip
+          python3 --version
+          python3.11 -m pip --version
 
       - name: Generate coverage report
         run: |
           echo "Generating coverage report for SonarQube..."
-          pip3 install -e ".[dev]"
+          python3.11 -m pip install -e ".[dev]"
-          pytest tests/ --cov=src/pote --cov-report=xml --cov-report=term || true
+          python3.11 -m pytest tests/ --cov=src/pote --cov-report=xml --cov-report=term || true
 
       - name: Run SonarScanner
         run: |