Retry: Update build-IGC public action

Previous attempt was mistakenly reverted.

- Add LLVM 16
- Remove 22.04 Ubuntu building; for public validate only on latest Ubuntu
- Remove unused `experimental` key
- Update SPIRV-Headers/Tools refs to use ToT

Author: pszymich

.github/workflows/build-IGC.yml

@@ -49,12 +49,9 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ubuntu_version: [ '22.04', '24.04' ]
-        llvm_ver: [ 14 ]
-        include:
-          - ubuntu_version: '22.04'
-            llvm_ver: 15
-            experimental: true
+        ubuntu_version: [ '24.04' ]
+        llvm_ver: [ 14, 15, 16 ]
+
     steps:
       - uses: actions/checkout@v3
       - name: cloning SPIRV-LLVM-Translator repository
@@ -99,14 +96,9 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ubuntu_version: [ '22.04', '24.04' ]
-        llvm_ver: [ 14 ]
+        ubuntu_version: [ '24.04' ]
+        llvm_ver: [ 14, 15, 16 ]
         compiler: [ gcc, clang ]
-        include:
-          - ubuntu_version: '22.04'
-            llvm_ver: 15
-            compiler: gcc
-            experimental: true
     steps:
       - uses: actions/checkout@v3
 
@@ -157,13 +149,13 @@ jobs:
         uses: actions/checkout@v3
         with:
           repository: KhronosGroup/SPIRV-Headers
-          ref: sdk-1.3.204.1
+          ref: main
           path: workspace/SPIRV-Headers
       - name:  Checkout the SPIRV-Headers
         uses: actions/checkout@v3
         with:
           repository: KhronosGroup/SPIRV-Tools
-          ref: sdk-1.3.204.1
+          ref: main
           path: workspace/SPIRV-Tools
       - name: get short hash
         id: igc-current-short-Hash