[MINOR][SQL] Remove unused checkForNumericExpr()

### What changes were proposed in this pull request?
In the PR, I propose to remove 2 unused methods: `checkForNumericExpr()` and `checkTypesInternal()`. Type checks of inputs in `Pmod` are performed by `BinaryArithmetic.checkInputDataTypes()`.

### Why are the changes needed?
To improve code maintenance.

### Does this PR introduce _any_ user-facing change?
No.

### How was this patch tested?
By running the related test suites:
```
$ build/sbt "sql/testOnly org.apache.spark.sql.SQLQueryTestSuite"
$ build/sbt "test:testOnly *ArithmeticExpressionSuite"
```

Closes #37740 from MaxGekk/rm-checkForNumericExpr.

Authored-by: Max Gekk <[email protected]>
Signed-off-by: Yuming Wang <[email protected]>

Author: MaxGekk

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

@@ -981,9 +981,6 @@ case class Pmod(
 
   override def symbol: String = "pmod"
 
-  protected def checkTypesInternal(t: DataType): TypeCheckResult =
-    TypeUtils.checkForNumericExpr(t, "pmod")
-
   override def inputType: AbstractDataType = NumericType
 
   override def nullable: Boolean = true

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/util/TypeUtils.scala

@@ -26,13 +26,6 @@ import org.apache.spark.sql.types._
  * Functions to help with checking for valid data types and value comparison of various types.
  */
 object TypeUtils {
-  def checkForNumericExpr(dt: DataType, caller: String): TypeCheckResult = {
-    if (dt.isInstanceOf[NumericType] || dt == NullType) {
-      TypeCheckResult.TypeCheckSuccess
-    } else {
-      TypeCheckResult.TypeCheckFailure(s"$caller requires numeric types, not ${dt.catalogString}")
-    }
-  }
 
   def checkForOrderingExpr(dt: DataType, caller: String): TypeCheckResult = {
     if (RowOrdering.isOrderable(dt)) {