Add canonical link to index.html

Author: RaspberryPi400

index.html

@@ -5,6 +5,7 @@
   <meta name="google-site-verification" content="aFn5C7ybPkOOcT1ymxpRGZ-J0aHOqjdFNcACj5poJb0" />
   <title>Study Guide Creator</title>
   <meta name="description" content="This website helps you create study guides and test yourself. You input the questions & answers, then take the test and get an instant score."/>
+  <link rel="canonical" href="https://raspberrypi400.github.io/Make-Your-Own-Study-Guide/" />
   <link rel="icon" type="image/x-icon" href="favicon.ico">
   <style>
     body { font-family: sans-serif; text-align: center; padding-top: 100px; }