Make Vigenere Cipher link point to the right file

README.md

@@ -68,7 +68,7 @@ required to complete them.
 | [Slider Design](./Projects/Slider-Design.md)                           | Display images using a slider control                     | 1-Beginner |
 | [Stopwatch App](./Projects/Stopwatch-App.md)                   | Count time spent on activities                            | 1-Beginner |
 | [TrueOrFalse](./Projects/True-or-False-App.md)                         | Identify the result of a conditional comparison           | 1-Beginner |
-| [Vigenere Cipher](./Projects/Vigenere-Cipher)                        | Encrypt text using the Vigenere Cypher                    | 1-Beginner |
+| [Vigenere Cipher](./Projects/Vigenere-Cipher.md)                        | Encrypt text using the Vigenere Cypher                    | 1-Beginner |
 | [Wind Chill](./Projects/Windchill-App.md)                              | Calculate the windchill factor from an actual temperature | 1-Beginner |
 | [Word Frequency](./Projects/Word-Frequency-App.md)                   | Calculate word frequency in a block of text               | 1-Beginner |