install llvm@15

Change-Id: I79aa47c1cd155bc095ed69986e6a8281f5015c4e

Author: rdementi

.github/workflows/macos-scan-build.yml

@@ -32,7 +32,7 @@ jobs:
 
     - name: install brew
       run: |
-        brew install llvm
+        brew install llvm@15
 
     - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
       with: