chore: Fallback to Spark for windows

Author: comphead

common/src/main/scala/org/apache/comet/CometConf.scala

@@ -251,7 +251,7 @@ object CometConf extends ShimCometConf {
   val COMET_EXEC_EXPAND_ENABLED: ConfigEntry[Boolean] =
     createExecEnabledConfig("expand", defaultValue = true)
   val COMET_EXEC_WINDOW_ENABLED: ConfigEntry[Boolean] =
-    createExecEnabledConfig("window", defaultValue = false)
+    createExecEnabledConfig("window", defaultValue = true)
   val COMET_EXEC_TAKE_ORDERED_AND_PROJECT_ENABLED: ConfigEntry[Boolean] =
     createExecEnabledConfig("takeOrderedAndProject", defaultValue = true)