fix(ci): Use apt.llvm.org for clang-format v22

The LLVM apt repo does have v22 packages (development branch). Use the
standard llvm.sh + apt-get approach with update-alternatives, same as
the original v20 setup but bumped to v22.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: antonis

.github/workflows/buildandtest.yml

@@ -53,20 +53,17 @@ jobs:
 
       # Default of ubuntu and apt packages are too old compared to macos packages.
       # This is required for using a newer version of clang-format.
-      - name: Setup clang V20
+      - name: Setup clang-format V22
         run: |
-          sudo bash -c "$(wget -O - https://apt.llvm.org/llvm.sh)" 20
-          sudo apt-get install -y clang-20 lld-20 lldb-20
+          sudo bash -c "$(wget -O - https://apt.llvm.org/llvm.sh)" 22
+          sudo apt-get install -y clang-22 clang-format-22 lld-22 lldb-22
 
-      - name: Set clang V20 as default
+      - name: Set clang-format V22 as default
         run: |
-          sudo update-alternatives --install /usr/bin/clang clang /usr/bin/clang-20 200
-          sudo update-alternatives --install /usr/bin/clang++ clang++ /usr/bin/clang++-20 200
+          sudo update-alternatives --install /usr/bin/clang clang /usr/bin/clang-22 200
+          sudo update-alternatives --install /usr/bin/clang++ clang++ /usr/bin/clang++-22 200
+          sudo update-alternatives --install /usr/bin/clang-format clang-format /usr/bin/clang-format-22 200
           clang --version
-
-      - name: Setup clang-format V22
-        run: |
-          pip install --break-system-packages clang-format==22.1.2
           clang-format --version
 
       - name: Install Swiftly and Swift