Fix Redirect so that redirect-rw take precedence over redirect-w (delta-io#4352)

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#### Which Delta project/connector is this regarding?
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- [x] Spark
- [ ] Standalone
- [ ] Flink
- [ ] Kernel
- [ ] Other (fill in here)

## Description

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When both redirect-rw and redirect-w configuration exist, we want
redirect-rw take precedence over redirect-w.

## How was this patch tested?
`TableRedirectSuite.scala`
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## Does this PR introduce _any_ user-facing changes?
No
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Author: ami7o

spark/src/main/scala/org/apache/spark/sql/delta/redirect/TableRedirect.scala

@@ -490,6 +490,10 @@ object RedirectFeature {
     mapper.readValue(configString, classOf[TableRedirectConfiguration])
   }
 
+  /**
+   * Get the current `TableRedirectConfiguration` object from the table properties.
+   * Note that the redirect-reader-writer takes precedence over redirect-writer-only.
+   */
   def getRedirectConfiguration(
       properties: Map[String, String]): Option[TableRedirectConfiguration] = {
     properties.get(DeltaConfigs.REDIRECT_READER_WRITER.key)
@@ -514,13 +518,12 @@ object RedirectFeature {
     }
   }
 
-  /** Get the current `TableRedirectConfiguration` object from the snapshot. */
+  /**
+   * Get the current `TableRedirectConfiguration` object from the snapshot.
+   * Note that the redirect-reader-writer takes precedence over redirect-writer-only.
+   */
   def getRedirectConfiguration(snapshot: Snapshot): Option[TableRedirectConfiguration] = {
-    if (RedirectWriterOnly.isFeatureSupported(snapshot)) {
-      RedirectWriterOnly.getRedirectConfiguration(snapshot.metadata)
-    } else {
-      RedirectReaderWriter.getRedirectConfiguration(snapshot.metadata)
-    }
+    getRedirectConfiguration(snapshot.metadata.configuration)
   }
 
   /** Determines whether `configs` contains redirect configuration. */

spark/src/test/scala/org/apache/spark/sql/delta/TableRedirectSuite.scala

@@ -25,6 +25,7 @@ import org.apache.spark.sql.delta.redirect.{
   EnableRedirectInProgress,
   NoRedirectRule,
   PathBasedRedirectSpec,
+  RedirectFeature,
   RedirectReaderWriter,
   RedirectReady,
   RedirectSpec,
@@ -396,4 +397,24 @@ class TableRedirectSuite extends QueryTest
           assert(result.length == 4)
     }
   }
+
+  test("test getRedirectConfiguration") {
+    val redirectSpec = new PathBasedRedirectSpec("sourcePath", "targetPath")
+    val properties1 = RedirectReaderWriter.generateRedirectMetadata(
+      PathBasedRedirectSpec.REDIRECT_TYPE,
+      EnableRedirectInProgress,
+      redirectSpec,
+      noRedirectRules = Set.empty)
+    val properties2 = RedirectWriterOnly.generateRedirectMetadata(
+      PathBasedRedirectSpec.REDIRECT_TYPE,
+      RedirectReady,
+      redirectSpec,
+      noRedirectRules = Set.empty)
+
+    val configuration = RedirectFeature.getRedirectConfiguration(properties1 ++ properties2)
+    assert(configuration.isDefined)
+    // redirect-reader-writer should be preferred over redirect-writer-only.
+    assert(JsonUtils.toJson(configuration.get) ==
+      properties1(DeltaConfigs.REDIRECT_READER_WRITER.key))
+  }
 }