Revert "[CI] Use llvm-toolchain-focal-17/ on the main branch (#2104)"

This reverts commit 93b6d57.

Author: svenvh

.github/workflows/check-code-style.yml

@@ -64,7 +64,7 @@ jobs:
         # launched, so, we need to setup llvm package to perform cmake
         # configuration step to generate that database
         curl -L "https://apt.llvm.org/llvm-snapshot.gpg.key" | sudo apt-key add -
-        echo "deb https://apt.llvm.org/focal/ llvm-toolchain-focal-17 main" | sudo tee -a /etc/apt/sources.list
+        echo "deb https://apt.llvm.org/focal/ llvm-toolchain-focal main" | sudo tee -a /etc/apt/sources.list
         sudo apt-get update
         sudo apt-get install -yqq \
             clang-format-${{ env.LLVM_VERSION }} clang-tidy-${{ env.LLVM_VERSION }} \

.github/workflows/check-in-tree-build.yml

@@ -51,7 +51,7 @@ jobs:
         run: |
           curl -L "https://apt.llvm.org/llvm-snapshot.gpg.key" | sudo apt-key add -
           curl -L "https://packages.lunarg.com/lunarg-signing-key-pub.asc" | sudo apt-key add -
-          echo "deb https://apt.llvm.org/focal/ llvm-toolchain-focal-17 main" | sudo tee -a /etc/apt/sources.list
+          echo "deb https://apt.llvm.org/focal/ llvm-toolchain-focal main" | sudo tee -a /etc/apt/sources.list
           echo "deb https://packages.lunarg.com/vulkan focal main" | sudo tee -a /etc/apt/sources.list
           sudo apt-get update
           sudo apt-get -yq --no-install-suggests --no-install-recommends install \

.github/workflows/check-out-of-tree-build.yml

@@ -44,7 +44,7 @@ jobs:
         run: |
           curl -L "https://apt.llvm.org/llvm-snapshot.gpg.key" | sudo apt-key add -
           curl -L "https://packages.lunarg.com/lunarg-signing-key-pub.asc" | sudo apt-key add -
-          echo "deb https://apt.llvm.org/focal/ llvm-toolchain-focal-17 main" | sudo tee -a /etc/apt/sources.list
+          echo "deb https://apt.llvm.org/focal/ llvm-toolchain-focal main" | sudo tee -a /etc/apt/sources.list
           echo "deb https://packages.lunarg.com/vulkan focal main" | sudo tee -a /etc/apt/sources.list
           sudo apt-get update
           sudo apt-get -yq --no-install-suggests --no-install-recommends install \