ci: clang: Use Clang 15

This commit updates the Clang workflow to build tests using Clang 15.

Signed-off-by: Stephanos Ioannidis <[email protected]>
(cherry picked from commit 39af513)

Author: stephanosio

.github/workflows/clang.yaml

@@ -20,7 +20,7 @@ jobs:
         platform: ["native_posix"]
     env:
       ZEPHYR_SDK_INSTALL_DIR: /opt/toolchains/zephyr-sdk-0.15.0
-      LLVM_TOOLCHAIN_PATH: /usr/lib/llvm-12
+      LLVM_TOOLCHAIN_PATH: /usr/lib/llvm-15
       COMMIT_RANGE: ${{ github.event.pull_request.base.sha }}..${{ github.event.pull_request.head.sha }}
       BASE_REF: ${{ github.base_ref }}
     outputs: