Install micromamba

Author: rgaiacs

action.yml

@@ -16,9 +16,9 @@ runs:
     - name: Create Pixi environment
       shell: bash
       run: pixi init
-    - name: Install Python
+    - name: Install Python and micromamba
       shell: bash
-      run: pixi add python=3.13
+      run: pixi add python=3.13 micromamba
     - name: Install repo2wasm
       shell: bash
       run: pixi add --pypi repo2wasm