Member constraints already covered all of E0482 already, so that error never occurred anymore

compiler/rustc_error_codes/src/error_codes/E0482.md

@@ -1,8 +1,10 @@
+#### Note: this error code is no longer emitted by the compiler.
+
 A lifetime of a returned value does not outlive the function call.
 
 Erroneous code example:
 
-```compile_fail,E0482
+```compile_fail,E0700
 fn prefix<'a>(
     words: impl Iterator<Item = &'a str>
 ) -> impl Iterator<Item = String> { // error!
@@ -41,7 +43,7 @@ fn prefix(
 
 A similar lifetime problem might arise when returning closures:
 
-```compile_fail,E0482
+```compile_fail,E0700
 fn foo(
     x: &mut Vec<i32>
 ) -> impl FnMut(&mut Vec<i32>) -> &[i32] { // error!