[SPARK-46241][PYTHON][CONNECT] Fix error handling routine so it wouldn't fall into infinite recursion

### What changes were proposed in this pull request?

Remove _display_server_stack_trace and always display error stack trace if we have one

### Why are the changes needed?

There is a certain codepath which can make existing error handling fall into infinite recursion. I.e. consider following codepath:

`[Some error happens] -> _handle_error -> _handle_rpc_error -> _display_server_stack_trace -> RuntimeConf.get -> SparkConnectClient.config -> [An error happens] -> _handle_error`.

There can be other similar codepaths

### Does this PR introduce _any_ user-facing change?

Gets rid of occasionally infinite recursive error handling (which can cause downgraded user experience)

### How was this patch tested?
N/A

### Was this patch authored or co-authored using generative AI tooling?
No

Closes #44144 from cdkrot/forbid_recursive_error_handling.

Authored-by: Alice Sayutina <[email protected]>
Signed-off-by: Hyukjin Kwon <[email protected]>

Author: cdkrot

python/pyspark/sql/connect/client/core.py

@@ -1520,20 +1520,6 @@ def _fetch_enriched_error(self, info: "ErrorInfo") -> Optional[pb2.FetchErrorDet
         except grpc.RpcError:
             return None
 
-    def _display_server_stack_trace(self) -> bool:
-        from pyspark.sql.connect.conf import RuntimeConf
-
-        conf = RuntimeConf(self)
-        try:
-            if conf.get("spark.sql.connect.serverStacktrace.enabled") == "true":
-                return True
-            return conf.get("spark.sql.pyspark.jvmStacktrace.enabled") == "true"
-        except Exception as e:  # noqa: F841
-            # Falls back to true if an exception occurs during reading the config.
-            # Otherwise, it will recursively try to get the conf when it consistently
-            # fails, ending up with `RecursionError`.
-            return True
-
     def _handle_rpc_error(self, rpc_error: grpc.RpcError) -> NoReturn:
         """
         Error handling helper for dealing with GRPC Errors. On the server side, certain
@@ -1567,7 +1553,7 @@ def _handle_rpc_error(self, rpc_error: grpc.RpcError) -> NoReturn:
                         info,
                         status.message,
                         self._fetch_enriched_error(info),
-                        self._display_server_stack_trace(),
+                        True,
                     ) from None
 
             raise SparkConnectGrpcException(status.message) from None