style: remove redundant main method

Author: vil02

src/main/java/com/thealgorithms/ciphers/AffineCipher.java

@@ -84,16 +84,4 @@ static String decryptCipher(String cipher) {
 
         return msg.toString();
     }
-
-    // Driver code
-    public static void main(String[] args) {
-        String msg = "AFFINE CIPHER";
-
-        // Calling encryption function
-        String cipherText = encryptMessage(msg.toCharArray());
-        System.out.println("Encrypted Message is : " + cipherText);
-
-        // Calling Decryption function
-        System.out.println("Decrypted Message is: " + decryptCipher(cipherText));
-    }
 }