Use mamba for conda in action

.github/workflows/build.yaml

@@ -25,11 +25,13 @@ jobs:
           channels: conda-forge,defaults
           channel-priority: strict
           show-channel-urls: true
+          miniforge-variant: Mambaforge
+          use-mamba: true
 
       - name: Update pip/wheel infrastructure
         shell: bash -l {0}
         run: |
-          conda install -y -q pip wheel
+          mamba install -y -q pip wheel
           pip install uv
 
       - name: Install dependencies