Remove redundant overrides

javascript/ql/lib/semmle/javascript/Files.qll

@@ -234,8 +234,6 @@ class File extends Container, @file {
   /** Gets a toplevel piece of JavaScript code in this file. */
   TopLevel getATopLevel() { result.getFile() = this }
 
-  override string toString() { result = Container.super.toString() }
-
   /** Gets the URL of this file. */
   override string getURL() { result = "file://" + this.getAbsolutePath() + ":0:0:0:0" }
 

javascript/ql/lib/semmle/javascript/frameworks/xUnit.qll

@@ -43,8 +43,6 @@ abstract private class BracketedListOfExpressions extends Expr {
  * An array expression viewed as a bracketed list of expressions.
  */
 private class ArrayExprIsABracketedListOfExpressions extends ArrayExpr, BracketedListOfExpressions {
-  override predicate isImpure() { ArrayExpr.super.isImpure() }
-
   /** Gets the `i`th element of this array literal. */
   override Expr getElement(int i) { result = ArrayExpr.super.getElement(i) }
 }