ubuntu 20 deprecated so remove. Point to correct cmake source dir

Author: pfeatherstone

.github/workflows/ci.yml

@@ -19,14 +19,6 @@ jobs:
     strategy:
       matrix:
         include:
-          - name: Ubuntu-20.04-GCC
-            os: ubuntu-20.04
-            cc: gcc
-            cxx: g++
-          - name: Ubuntu-20.04-Clang
-            os: ubuntu-20.04
-            cc: clang
-            cxx: clang++
           - name: Ubuntu-22.04-GCC
             os: ubuntu-22.04
             cc: gcc
@@ -81,7 +73,7 @@ jobs:
 
       - name: Run CMake configuration and build
         run: |
-          "${{ env.CMAKE_BIN }}" . -B build -G Ninja \
+          "${{ env.CMAKE_BIN }}" examples -B build -G Ninja \
             -DCMAKE_BUILD_TYPE=RelWithDebInfo \
             -DCMAKE_C_COMPILER=${{ matrix.cc }} \
             -DCMAKE_CXX_COMPILER=${{ matrix.cxx }}