[BAEL-3518] Removed the CheckIntegerInput because its removed from the article (#8228)

core-java-modules/core-java-string-operations/src/main/java/com/baeldung/isnumeric/CheckIntegerInput.java

@@ -1,18 +0,0 @@
-package com.baeldung.isnumeric;
-
-import java.util.Scanner;
-
-public class CheckIntegerInput {
-
-    public static void main(String[] args) {
-        try (Scanner scanner = new Scanner(System.in)) {
-            System.out.println("Enter an integer : ");
-
-            if (scanner.hasNextInt()) {
-                System.out.println("You entered : " + scanner.nextInt());
-            } else {
-                System.out.println("The input is not an integer");
-            }
-        }
-    }
-}