Test cases project euler 6 (TheAlgorithms#1570)

* 📦 NEW: Added solution for ProjectEuler-007

* 🐛 FIX: Spelling mistake fixes

* 👌 IMPROVE: changed variable name from `inc` to `candidateValue` and thrown error in case of invalid input

* 👌 IMPROVE: Modified the code

* 👌 IMPROVE: Added test case for ProjectEuler Problem001

* 👌 IMPROVE: Added test cases for Project Euler Problem 4

* 👌 IMPROVE: auto prettier fixes

* 👌 IMPROVE: added test cases for project euler problem 6

* Updated Documentation in README.md

* Updated Documentation in README.md

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Co-authored-by: Omkarnath Parida <[email protected]>
Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>

Author: 3 people

Project-Euler/test/Problem006.test.js

@@ -0,0 +1,11 @@
+import { squareDifference } from '../Problem006.js'
+
+describe('Square Difference', () => {
+  test('difference between the sum of the squares of the first ten natural numbers and the square of the sum', () => {
+    expect(squareDifference(10)).toBe(2640)
+  })
+  // Project Euler Condition Check
+  test('difference between the sum of the squares of the first one hundred natural numbers and the square of the sum', () => {
+    expect(squareDifference()).toBe(25164150)
+  })
+})