ci: upgrade to llvm 19

.github/workflows/go.yml

@@ -5,9 +5,9 @@ name: Go
 
 on:
   push:
-    branches: [ "**" ]
+    branches: ["**"]
   pull_request:
-    branches: [ "**" ]
+    branches: ["**"]
 
 jobs:
   test:
@@ -17,7 +17,7 @@ jobs:
         os:
           - macos-latest
           - ubuntu-24.04
-        llvm: [18]
+        llvm: [19]
     runs-on: ${{matrix.os}}
     defaults:
       run:
@@ -38,7 +38,7 @@ jobs:
       - name: Set up Go
         uses: ./.github/actions/setup-go
         with:
-          go-version: '1.24.0'
+          go-version: "1.24.0"
 
       - name: Build
         run: go build -v ./...