Update Python version to 3.13 for theme compatibility

Co-authored-by: mmcky <8263752+mmcky@users.noreply.github.com>

Author: Copilot

.github/workflows/ci.yml

@@ -14,7 +14,7 @@ jobs:
           auto-update-conda: true
           auto-activate-base: true
           miniconda-version: 'latest'
-          python-version: "3.12"
+          python-version: "3.13"
           environment-file: environment.yml
           activate-environment: quantecon
       - name: Install latex dependencies

environment.yml

@@ -2,7 +2,7 @@ name: quantecon
 channels:
   - default
 dependencies:
-  - python=3.12
+  - python=3.13
   - anaconda=2024.10
   - pip
   - pip: