[SPARK-33292][SQL] Make Literal ArrayBasedMapData string representati…

…on disambiguous

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

This PR aims to wrap `ArrayBasedMapData` literal representation with `map(...)`.

### Why are the changes needed?

Literal ArrayBasedMapData has inconsistent string representation from `LogicalPlan` to `Optimized Logical Plan/Physical Plan`. Also, the representation at `Optimized Logical Plan` and `Physical Plan` is ambiguous like `[1 AS a#0, keys: [key1], values: [value1] AS b#1]`.

**BEFORE**
```scala
scala> spark.version
res0: String = 2.4.7

scala> sql("SELECT 1 a, map('key1', 'value1') b").explain(true)
== Parsed Logical Plan ==
'Project [1 AS a#0, 'map(key1, value1) AS b#1]
+- OneRowRelation

== Analyzed Logical Plan ==
a: int, b: map<string,string>
Project [1 AS a#0, map(key1, value1) AS b#1]
+- OneRowRelation

== Optimized Logical Plan ==
Project [1 AS a#0, keys: [key1], values: [value1] AS b#1]
+- OneRowRelation

== Physical Plan ==
*(1) Project [1 AS a#0, keys: [key1], values: [value1] AS b#1]
+- Scan OneRowRelation[]
```

**AFTER**
```scala
scala> spark.version
res0: String = 3.1.0-SNAPSHOT

scala> sql("SELECT 1 a, map('key1', 'value1') b").explain(true)
== Parsed Logical Plan ==
'Project [1 AS a#4, 'map(key1, value1) AS b#5]
+- OneRowRelation

== Analyzed Logical Plan ==
a: int, b: map<string,string>
Project [1 AS a#4, map(key1, value1) AS b#5]
+- OneRowRelation

== Optimized Logical Plan ==
Project [1 AS a#4, map(keys: [key1], values: [value1]) AS b#5]
+- OneRowRelation

== Physical Plan ==
*(1) Project [1 AS a#4, map(keys: [key1], values: [value1]) AS b#5]
+- *(1) Scan OneRowRelation[]
```

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

Yes. This changes the query plan's string representation in `explain` command and UI. However, this is a bug fix.

### How was this patch tested?

Pass the CI with the newly added test case.

Closes apache#30190 from dongjoon-hyun/SPARK-33292.

Authored-by: Dongjoon Hyun <dhyun@apple.com>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/literals.scala

@@ -297,6 +297,7 @@ case class Literal (value: Any, dataType: DataType) extends LeafExpression {
   override def toString: String = value match {
     case null => "null"
     case binary: Array[Byte] => s"0x" + DatatypeConverter.printHexBinary(binary)
+    case d: ArrayBasedMapData => s"map(${d.toString})"
     case other => other.toString
   }
 

sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/LiteralExpressionSuite.scala

@@ -209,6 +209,7 @@ class LiteralExpressionSuite extends SparkFunSuite with ExpressionEvalHelper {
     }
     checkMapLiteral(Map("a" -> 1, "b" -> 2, "c" -> 3))
     checkMapLiteral(Map("1" -> 1.0, "2" -> 2.0, "3" -> 3.0))
+    assert(Literal.create(Map("a" -> 1)).toString === "map(keys: [a], values: [1])")
   }
 
   test("struct") {