Upgrade to LLVM 19

Author: onelxj

.github/workflows/code_formatting.yaml

@@ -33,7 +33,7 @@ concurrency:
 jobs:
   check-code-format:
     name: Code Formatting Check
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
         with:
@@ -56,4 +56,4 @@ jobs:
       # is also used by other repos that submodule this repo.
       - uses: ./check-code-style
         with:
-          os: ubuntu-20.04
+          os: ubuntu-latest

check-code-style/action.yml

@@ -12,11 +12,11 @@ runs:
   using: "composite"
   steps:
     - name: Install code checking tools if on Ubuntu
-      if: inputs.os == 'ubuntu-latest' || inputs.os == 'ubuntu-20.04'
+      if: inputs.os == 'ubuntu-latest'
       run: |
         # Install Clang (including clang-format) through LLVM's preferred mechanism:
         #   https://apt.llvm.org/
-        CLANG_VERSION=14
+        CLANG_VERSION=19
         wget https://apt.llvm.org/llvm.sh
         chmod +x llvm.sh
         sudo ./llvm.sh ${CLANG_VERSION}