docs: add file for Classification with a Boosted Treed Model and snippet for preparing sample data (#1135)

* docs: add snippet for Linear Regression tutorial Explain Prediction section

* add snippet that prepares census sample data

* remove file changes

* rename file due to typo

Author: rey-esp

samples/snippets/classification_boosted_tree_model_test.py

@@ -0,0 +1,42 @@
+# Copyright 2024 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+def test_boosted_tree_model(random_model_id: str) -> None:
+    # your_model_id = random_model_id
+    # [START bigquery_dataframes_bqml_boosted_tree_prepare]
+    import bigframes.pandas as bpd
+
+    input_data = bpd.read_gbq(
+        "bigquery-public-data.ml_datasets.census_adult_income",
+        columns=(
+            "age",
+            "workclass",
+            "marital_status",
+            "education_num",
+            "occupation",
+            "hours_per_week",
+            "income_bracket",
+            "functional_weight",
+        ),
+    )
+    input_data["dataframe"] = bpd.Series("training", index=input_data.index,).case_when(
+        [
+            (((input_data["functional_weight"] % 10) == 8), "evaluation"),
+            (((input_data["functional_weight"] % 10) == 9), "prediction"),
+        ]
+    )
+    del input_data["functional_weight"]
+    # [END bigquery_dataframes_bqml_boosted_tree_prepare]
+    assert input_data is not None