refactor: Use raw string in regex (#4016)

* refactor: Use raw string in regex

* np.NaN was removed in the NumPy 2.0

* Move default python version to 3.10

* Move back default python version to 3.9

* Remove version mistmatched tes notebooks

.cloud-build/execute_changed_notebooks_helper.py

@@ -238,7 +238,7 @@ def _get_notebook_python_version(notebook_path: str) -> str:
 
             # Look for the python version specification pattern
             re_match = re.search(
-                "python version = (\d+\.\d+)", markdown, flags=re.IGNORECASE
+                r"python version = (\d+\.\d+)", markdown, flags=re.IGNORECASE
             )
             if re_match:
                 # get the version number

.cloud-build/test_notebook_vm.txt

@@ -1,5 +1,3 @@
-notebooks/official/vizier/gapic-vizier-multi-objective-optimization.ipynb
-notebooks/official/pipelines/lightweight_functions_component_io_kfp.ipynb
 notebooks/official/ml_metadata/sdk-metric-parameter-tracking-for-locally-trained-models.ipynb
 notebooks/official/custom/custom-tabular-bq-managed-dataset.ipynb
 .cloud-build/tests/python_version_test.ipynb

notebooks/official/custom/custom-tabular-bq-managed-dataset.ipynb

@@ -409,7 +409,7 @@
         "df = bq_client.list_rows(table).to_dataframe()\n",
         "\n",
         "# Drop unusable rows\n",
-        "df = df.replace(to_replace=NA_VALUES, value=np.NaN).dropna()\n",
+        "df = df.replace(to_replace=NA_VALUES, value=np.nan).dropna()\n",
         "\n",
         "# Convert categorical columns to numeric\n",
         "df[\"island\"], _ = pd.factorize(df[\"island\"])\n",