[VL] Remove dead config spark.gluten.velox.fs.s3a.connect.timeout (#11810)

The config `spark.gluten.velox.fs.s3a.connect.timeout` was originally
introduced in GLUTEN-5659 and explicitly read by ConfigExtractor.cc to
set the S3 TCP connect timeout (connectTimeoutMs).

In GLUTEN-9182, ConfigExtractor.cc was refactored to use a suffix-map
approach reading `spark.hadoop.fs.s3a.connection.establish.timeout`
for connectTimeoutMs and `spark.hadoop.fs.s3a.connection.timeout` for
requestTimeoutMs. The old key was never cleaned up, leaving
`AWS_S3_CONNECT_TIMEOUT` defined in VeloxConfig.scala but never
referenced, and the key forwarded into the native conf map but never
consumed by any C++ code.

Remove the config definition, its entries in nativeKeys and
getNativeBackendConf defaults, and the documentation row.

Author: xumingming

backends-velox/src/main/scala/org/apache/gluten/config/VeloxConfig.scala

@@ -551,12 +551,6 @@ object VeloxConfig extends ConfigRegistry {
       .stringConf
       .createWithDefault("legacy")
 
-  val AWS_S3_CONNECT_TIMEOUT =
-    buildConf("spark.gluten.velox.fs.s3a.connect.timeout")
-      .doc("Timeout for AWS s3 connection.")
-      .stringConf
-      .createWithDefault("200s")
-
   val VELOX_ORC_SCAN_ENABLED =
     buildConf("spark.gluten.sql.columnar.backend.velox.orc.scan.enabled")
       .doc("Enable velox orc scan. If disabled, vanilla spark orc scan will be used.")

docs/velox-configuration.md

@@ -78,7 +78,6 @@ nav_order: 16
 | spark.gluten.sql.enable.enhancedFeatures                                         | true              | Enable some features including iceberg native write and other features.                                                                                                                                                                                                                                                                                                                                                                               |
 | spark.gluten.sql.rewrite.castArrayToString                                       | true              | When true, rewrite `cast(array as String)` to `concat('[', array_join(array, ', ', null), ']')` to allow offloading to Velox.                                                                                                                                                                                                                                                                                                                         |
 | spark.gluten.velox.castFromVarcharAddTrimNode                                    | false             | If true, will add a trim node which has the same sementic as vanilla Spark to CAST-from-varchar.Otherwise, do nothing.                                                                                                                                                                                                                                                                                                                                |
-| spark.gluten.velox.fs.s3a.connect.timeout                                        | 200s              | Timeout for AWS s3 connection.                                                                                                                                                                                                                                                                                                                                                                                                                        |
 
 ## Gluten Velox backend *experimental* configurations
 

gluten-substrait/src/main/scala/org/apache/gluten/config/GlutenConfig.scala

@@ -494,7 +494,6 @@ object GlutenConfig extends ConfigRegistry {
     SPARK_S3_CONNECTION_MAXIMUM,
     SPARK_S3_ENDPOINT_REGION,
     SPARK_S3_AWS_IMDS_ENABLED,
-    "spark.gluten.velox.fs.s3a.connect.timeout",
     "spark.gluten.velox.fs.s3a.retry.mode",
     "spark.gluten.velox.awsSdkLogLevel",
     "spark.gluten.velox.s3UseProxyFromEnv",
@@ -604,7 +603,6 @@ object GlutenConfig extends ConfigRegistry {
       (SPARK_S3_USE_INSTANCE_CREDENTIALS, "false"),
       (SPARK_S3_RETRY_MAX_ATTEMPTS, "20"),
       (SPARK_S3_CONNECTION_MAXIMUM, "15"),
-      ("spark.gluten.velox.fs.s3a.connect.timeout", "200s"),
       ("spark.gluten.velox.fs.s3a.retry.mode", "legacy"),
       (
         "spark.gluten.sql.columnar.backend.velox.IOThreads",