update GitHub actions VMs to ubuntu-latest (#631)

### Description
This updates the virtual machines used to run the test suite on GitHub's
cloud infrastructure to use `ubuntu-latest` (currently Ubuntu 22.04).

See:
https://github.com/actions/runner-images?tab=readme-ov-file#available-images

### Related issues
N/A

### Checklist
_Before this pull request can be reviewed, all of these tasks should be
completed. Denote completed tasks with an `x` inside the square brackets
`[ ]` in the Markdown source below:_
- [x] I have added a description (see above).
- [ ] I have added a link to any related issues see (see above).
- [x] I have read the [Contributing
Guide](https://github.com/quokka-astro/quokka/blob/development/CONTRIBUTING.md).
- [ ] I have added tests for any new physics that this PR adds to the
code.
- [ ] I have tested this PR on my local computer and all tests pass.
- [ ] I have manually triggered the GPU tests with the magic comment
`/azp run`.
- [ ] I have requested a reviewer for this PR.

.github/workflows/checkpoint-restart.yml

@@ -19,7 +19,7 @@ env:
 
 jobs:
   test:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
 
     steps:
     - uses: actions/checkout@v4

.github/workflows/cmake.yml

@@ -19,11 +19,7 @@ env:
 
 jobs:
   build:
-    # The CMake configure and build commands are platform agnostic and should work equally
-    # well on Windows or Mac.  You can convert this to a matrix build if you need
-    # cross-platform coverage.
-    # See: https://docs.github.com/en/free-pro-team@latest/actions/learn-github-actions/managing-complex-workflows#using-a-build-matrix
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
 
     steps:
     - uses: actions/checkout@v4
@@ -37,7 +33,7 @@ jobs:
       run: cmake -E make_directory ${{runner.workspace}}/build
 
     - name: Install dependencies
-      run: sudo apt-get update && sudo apt-get install gcc-11 g++-11 python3-dev python3-numpy python3-matplotlib python3-pip lcov libopenmpi-dev libhdf5-mpi-dev ccache libboost-dev
+      run: sudo apt-get update && sudo apt-get install gcc-11 g++-11 python3-dev python3-numpy python3-matplotlib python3-pip libopenmpi-dev libhdf5-mpi-dev
 
     - name: Configure CMake
       # Use a bash shell so we can use the same syntax for environment variable

.github/workflows/hip.yml

@@ -16,7 +16,7 @@ concurrency:
 jobs:
   tests-hip:
     name: HIP ROCm C++17
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4
       with:

.github/workflows/warnings.yml

@@ -19,7 +19,7 @@ env:
 
 jobs:
   build:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
 
     steps:
     - uses: actions/checkout@v4
@@ -33,7 +33,7 @@ jobs:
       run: cmake -E make_directory ${{runner.workspace}}/build
 
     - name: Install dependencies
-      run: sudo apt-get update && sudo apt-get install gcc-11 g++-11 python3-dev python3-numpy python3-matplotlib python3-pip lcov libopenmpi-dev libhdf5-mpi-dev ccache libboost-dev
+      run: sudo apt-get update && sudo apt-get install gcc-11 g++-11 python3-dev python3-numpy python3-matplotlib python3-pip libopenmpi-dev libhdf5-mpi-dev
 
     - name: Configure CMake
       # Use a bash shell so we can use the same syntax for environment variable