Pin intake-esm for Python3.9 (#86)

### What kind of change does this PR introduce?

* pins `intake-esm` (needed for `xscen` and Python3.9)

### Does this PR introduce a breaking change?

No.

### Other information:

.github/workflows/main.yml

@@ -71,6 +71,10 @@ jobs:
           create-args: >-
             mamba
             python=${{ matrix.python-version }}
+      - name: Downgrade intake-esm (for xscen)
+        if: matrix.python-version == '3.9'
+        run: |
+          micromamba install -y intake-esm=2023.11.10
       - name: Conda and Mamba versions
         run: |
           mamba --version

environment.yml

@@ -6,11 +6,11 @@ dependencies:
   # Don't forget to sync changes between environment.yml, environment-dev.yml, and pyproject.toml!
   # Main packages
   - numpy
-  - pooch >=1.8.0\
-  - pydantic >=2.0,<2.5.3
+  - pooch >=1.8.0
+  - pydantic >=2.0,<2.5.3  # FIXME: Remove pin once our dependencies (xclim, xscen) support pydantic 2.5.3
   - statsmodels
   - xarray
-  - xclim >=0.47.0
+  - xclim >=0.47.0  # FIXME: Remove pin once our dependencies (xclim, xscen) support pandas 2.2.0
   - xscen >=0.7.1
   - pip
   - pip: