Pin sklearn version to 1.7.*

This avoids getting errors in PGI notebooks due to incompatibility of
SimPEG v0.25.0 and sklearn 1.8.0. See simpeg/simpeg#1742 for reference.

Author: santisoler

environment.yml

@@ -13,7 +13,7 @@ dependencies:
   - simpeg==0.25.*
   - discretize==0.12.*
   - choclo==0.3.*
-  - scikit-learn
+  - scikit-learn==1.7.*
   - pymatsolver
   # Code style
   - ruff