Revert "Rust: add Callable::getParam and CallExprBase::getArg shortcuts"

This reverts commit c70decb.

Author: redsun82

rust/ql/.generated.list

@@ -28,7 +28,5 @@ module Impl {
   class CallExprBase extends Generated::CallExprBase {
     /** Gets the static target of this call, if any. */
     Callable getStaticTarget() { none() } // overridden by subclasses, but cannot be made abstract
-
-    override Expr getArg(int index) { result = this.getArgList().getArg(index) }
   }
 }

rust/ql/.gitattributes

@@ -1,3 +1,4 @@
+// generated by codegen, remove this comment if you wish to edit this file
 /**
  * This module provides a hand-modifiable wrapper around the generated class `Callable`.
  *
@@ -15,7 +16,5 @@ module Impl {
   /**
    * A callable. Either a `Function` or a `ClosureExpr`.
    */
-  class Callable extends Generated::Callable {
-    override Param getParam(int index) { result = this.getParamList().getParam(index) }
-  }
+  class Callable extends Generated::Callable { }
 }