simplify the ci to run all examples

.github/workflows/rust.yml

@@ -136,22 +136,10 @@ jobs:
           rust-version: stable
       - name: Run examples
         run: |
-          # test datafusion-sql examples
-          cargo run --example sql
-          # test datafusion-examples
-          cargo run --example avro_sql
-          cargo run --example csv_sql
-          cargo run --example custom_datasource
-          cargo run --example dataframe
-          cargo run --example dataframe_in_memory
-          cargo run --example deserialize_to_struct
-          cargo run --example expr_api
-          cargo run --example parquet_sql
-          cargo run --example parquet_sql_multiple_files
-          cargo run --example memtable
-          cargo run --example rewrite_expr
-          cargo run --example simple_udf
-          cargo run --example simple_udaf
+          for example in $(ls datafusion-examples/examples/*.rs); do
+            example_name=$(basename "$example" .rs)
+            cargo run --example "$example_name"
+          done
       - name: Verify Working Directory Clean
         run: git diff --exit-code