Merge pull request #370 from philwareham/snyk-upgrade-04379492bf0e3f5c52b0741dc71d9e7c

[Snyk] Upgrade prismjs from 1.19.0 to 1.20.0

Author: philwareham

package.json

@@ -50,7 +50,7 @@
     "bootstrap": "3.4.1",
     "jquery": "3.4.1",
     "jquery-ui-dist": "1.12.1",
-    "prismjs": "1.19.0",
+    "prismjs": "1.20.0",
     "scrollspy-js": "0.1.3"
   },
   "optionalDependencies": {