Bump mamba-org/provision-with-micromamba from 14 to 15 (#418)

Bumps [mamba-org/provision-with-micromamba](https://github.com/mamba-org/provision-with-micromamba) from 14 to 15.
- [Release notes](https://github.com/mamba-org/provision-with-micromamba/releases)
- [Commits](mamba-org/provision-with-micromamba@v14...v15)

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

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/ci.yaml

@@ -36,7 +36,7 @@ jobs:
         run: |
           echo "PYTHON_VERSION=${{ matrix.python-version }}" >> $GITHUB_ENV
       - name: Set up conda environment
-        uses: mamba-org/provision-with-micromamba@v14
+        uses: mamba-org/provision-with-micromamba@v15
         with:
           environment-file: ci/environment.yml
           environment-name: cf_xarray_test
@@ -76,7 +76,7 @@ jobs:
         run: |
           echo "PYTHON_VERSION=${{ matrix.python-version }}" >> $GITHUB_ENV
       - name: Set up conda environment
-        uses: mamba-org/provision-with-micromamba@v14
+        uses: mamba-org/provision-with-micromamba@v15
         with:
           environment-file: ci/environment.yml
           environment-name: cf_xarray_test
@@ -111,7 +111,7 @@ jobs:
           # need to fetch all tags to get a correct version
           fetch-depth: 0  # fetch all branches and tags
       - name: Set up conda environment
-        uses: mamba-org/provision-with-micromamba@v14
+        uses: mamba-org/provision-with-micromamba@v15
         with:
           environment-file: ci/environment-no-optional-deps.yml
           environment-name: cf_xarray_test
@@ -139,7 +139,7 @@ jobs:
         with:
           fetch-depth: 0 # Fetch all history for all branches and tags.
       - name: Set up conda environment
-        uses: mamba-org/provision-with-micromamba@v14
+        uses: mamba-org/provision-with-micromamba@v15
         with:
           environment-file: ci/environment.yml
           environment-name: cf_xarray_test

.github/workflows/upstream-dev-ci.yaml

@@ -38,7 +38,7 @@ jobs:
         run: |
           echo "PYTHON_VERSION=${{ matrix.python-version }}" >> $GITHUB_ENV
       - name: Set up conda environment
-        uses: mamba-org/provision-with-micromamba@v14
+        uses: mamba-org/provision-with-micromamba@v15
         with:
           environment-file: ci/upstream-dev-env.yml
           environment-name: cf_xarray_test