Merge pull request github#3420 from max-schaefer/js/fix-missing-triple-backtick

Approved by asgerf

Author: semmle-qlci

javascript/ql/src/semmle/javascript/Expr.qll

@@ -303,6 +303,7 @@ class Label extends @label, Identifier, Expr {
  * 3n        // BigInt literal
  * "hello"   // string literal
  * /jsx?/    // regular-expression literal
+ * ```
  */
 class Literal extends @literal, Expr {
   /** Gets the value of this literal, as a string. */