Pin setup-micromamba action to v2 (#424)

Author: mcbarton

.github/workflows/deploy-github-page.yml

@@ -31,7 +31,7 @@ jobs:
           fetch-depth: 0
 
       - name: install mamba
-        uses: mamba-org/setup-micromamba@main
+        uses: mamba-org/setup-micromamba@v2
         with:
           environment-file: environment-wasm-build.yml
           init-shell: bash

.github/workflows/main.yml

@@ -66,7 +66,7 @@ jobs:
           fetch-depth: 0
 
       - name: install mamba
-        uses: mamba-org/setup-micromamba@main
+        uses: mamba-org/setup-micromamba@v2
         with:
           environment-file: environment-dev.yml
           init-shell: >-
@@ -211,7 +211,7 @@ jobs:
           fetch-depth: 0
 
       - name: install mamba
-        uses: mamba-org/setup-micromamba@main
+        uses: mamba-org/setup-micromamba@v2
         with:
           environment-file: environment-wasm-build.yml
           init-shell: bash