Rust: Remove redundant model.

Author: geoffw0

rust/ql/lib/codeql/rust/frameworks/stdlib/core.model.yml

@@ -18,7 +18,6 @@ extensions:
       - ["<core::result::Result>::into_iter", "Argument[self].Element", "ReturnValue.Element", "value", "manual"]
       - ["<_ as core::iter::traits::iterator::Iterator>::for_each", "Argument[self].Element", "Argument[0].Parameter[0]", "value", "manual"]
       - ["<_ as core::iter::traits::iterator::Iterator>::nth", "Argument[self].Element", "ReturnValue.Field[core::option::Option::Some(0)]", "value", "manual"]
-      - ["<_ as core::iter::traits::iterator::Iterator>::next", "Argument[self]", "ReturnValue.Future.Field[core::option::Option::Some(0)]", "taint", "manual"]
       - ["<_ as core::iter::traits::iterator::Iterator>::next", "Argument[self].Element", "ReturnValue.Field[core::option::Option::Some(0)]", "value", "manual"]
       - ["<_ as core::iter::traits::iterator::Iterator>::next", "Argument[self].Element", "ReturnValue.Field[core::option::Option::Some(0)].Field[core::result::Result::Ok(0)]", "value", "manual"]
       - ["<_ as core::iter::traits::iterator::Iterator>::collect", "Argument[self].Element", "ReturnValue.Element", "value", "manual"]