Bump mamba-org/setup-micromamba from 1 to 2

Bumps [mamba-org/setup-micromamba](https://github.com/mamba-org/setup-micromamba) from 1 to 2.
- [Release notes](https://github.com/mamba-org/setup-micromamba/releases)
- [Commits](mamba-org/setup-micromamba@v1...v2)

---
updated-dependencies:
- dependency-name: mamba-org/setup-micromamba
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/build.yml

@@ -64,15 +64,15 @@ jobs:
       - name: environment setup
         id: env-setup
         continue-on-error: true
-        uses: mamba-org/setup-micromamba@v1
+        uses: mamba-org/setup-micromamba@v2
         with:
           environment-file: environment.yml
           cache-environment: true
           cache-environment-key: "build-${{env.TODAY}}"
 
       - name: retry environment set up if failed
         if: steps.env-setup.outcome == 'failure'
-        uses: mamba-org/setup-micromamba@v1
+        uses: mamba-org/setup-micromamba@v2
         with:
           download-micromamba: false
           environment-file: environment.yml