Chore: Cleanup how datafusion session config is created (#289)

core/src/execution/jni_api.rs

@@ -219,15 +219,11 @@ fn prepare_datafusion_session_context(
     // Get Datafusion configuration from Spark Execution context
     // can be configured in Comet Spark JVM using Spark --conf parameters
     // e.g: spark-shell --conf spark.datafusion.sql_parser.parse_float_as_decimal=true
-    let df_config = conf
-        .iter()
-        .filter(|(k, _)| k.starts_with("datafusion."))
-        .map(|kv| (kv.0.to_owned(), kv.1.to_owned()))
-        .collect::<Vec<(String, String)>>();
-
-    let session_config =
-        SessionConfig::from_string_hash_map(std::collections::HashMap::from_iter(df_config))?
-            .with_batch_size(batch_size);
+    let mut session_config = SessionConfig::new().with_batch_size(batch_size);
+
+    for (key, value) in conf.iter().filter(|(k, _)| k.starts_with("datafusion.")) {
+        session_config = session_config.set_str(key, value);
+    }
 
     let runtime = RuntimeEnv::new(rt_config).unwrap();