merge: Round-trip testing for Atbash cipher (TheAlgorithms#958)

- fix the test description

Author: trasherdk

Ciphers/test/Atbash.test.js

@@ -1,7 +1,7 @@
 import Atbash from '../Atbash'
 
 describe('Testing Atbash function', () => {
-  it('Test - 1, passing the non-string as an argument', () => {
+  it('Test - 1, passing a non-string as an argument', () => {
     expect(() => Atbash(0x345)).toThrow()
     expect(() => Atbash(123)).toThrow()
     expect(() => Atbash(123n)).toThrow()
@@ -10,8 +10,9 @@ describe('Testing Atbash function', () => {
     expect(() => Atbash([])).toThrow()
   })
 
-  it('Test - 2, passing all alphabets', () => {
-    expect(Atbash('HELLO WORLD')).toBe('SVOOL DLIOW')
-    expect(Atbash('The quick brown fox jumps over the lazy dog')).toBe('Gsv jfrxp yildm ulc qfnkh levi gsv ozab wlt')
+  it('Test - 2, passing a string as an argument', () => {
+    const clearText = 'The quick brown fox jumps over the lazy dog'
+    const cryptText = Atbash(clearText)
+    expect(Atbash(cryptText)).toBe(clearText)
   })
 })