Update pin of pandas instead of narwhals

Author: marthacryan

test_requirements/requirements_39_pandas_2_optional.txt

@@ -1,5 +1,5 @@
 requests==2.25.1
-pandas==2.2.0
+pandas==2.2.3
 numpy==1.22.4
 xarray==0.17.0
 statsmodels
@@ -21,6 +21,6 @@ vaex
 pydantic<=1.10.11 # for vaex, see https://github.com/vaexio/vaex/issues/2384
 polars[timezone]
 pyarrow
-narwhals==1.25.0
+narwhals>=1.15.1
 polars
 anywidget==0.9.13