updating CI

.github/workflows/amalgamate-ubuntu24.yml

@@ -1,4 +1,4 @@
-name: Amalgamate Ubuntu 20.04 CI (GCC 9)
+name: Amalgamate Ubuntu 24.04 CI
 
 on: [push, pull_request]
 

.github/workflows/ubuntu20.yml

@@ -1,21 +0,0 @@
-name: Ubuntu 20.04 CI (GCC 9)
-
-on: [push, pull_request]
-
-jobs:
-  ubuntu-build:
-    runs-on: ubuntu-20.04
-    steps:
-      - uses: actions/checkout@v4
-      - name: Use cmake
-        run: |
-          mkdir build &&
-          cd build &&
-          cmake  ${{matrix.cxx}} ${{matrix.arch}} -DFASTFLOAT_TEST=ON -DCMAKE_INSTALL_PREFIX:PATH=destination ..  &&
-          cmake --build .   &&
-          ctest --output-on-failure  &&
-          cmake --install . &&
-          cd ../tests/installation_tests/find &&
-          mkdir build && cd build && cmake -DCMAKE_INSTALL_PREFIX:PATH=../../../build/destination .. &&  cmake --build . &&
-          cd ../../issue72_installation  &&
-          mkdir build && cd build && cmake -DCMAKE_INSTALL_PREFIX:PATH=../../../build/destination .. &&  cmake --build .

.github/workflows/ubuntu24-cxx20.yml

@@ -1,10 +1,10 @@
-name: Ubuntu 20.04 CI (C++20)
+name: Ubuntu 24.04 CI
 
 on: [push, pull_request]
 
 jobs:
   ubuntu-build:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-24.04
     strategy:
       fail-fast: false
     steps:

.github/workflows/ubuntu24-fastmath.yml

@@ -1,10 +1,10 @@
-name: Ubuntu 20.04 CI (GCC 9, fast-math)
+name: Ubuntu 24.04 CI (fast-math)
 
 on: [push, pull_request]
 
 jobs:
   ubuntu-build:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-24.04
     steps:
       - uses: actions/checkout@v4
       - name: Use cmake