Specialise G-ADOPT smoke tests for main and release

Author: connorjward

.github/workflows/core.yml

@@ -359,7 +359,7 @@ jobs:
           matrix.arch == 'default'
         run: |
           . venv/bin/activate
-          git clone --depth 1 https://github.com/g-adopt/g-adopt.git g-adopt-repo
+          git clone --depth 1 https://github.com/g-adopt/g-adopt.git g-adopt-repo --branch ${{ inputs.target_branch }}
           pip install --verbose ./g-adopt-repo
           make -C g-adopt-repo/demos/mantle_convection/base_case check
         timeout-minutes: 5