Fill in tracking issue for WHERE_CLAUSES_OBJECT_SAFETY future compat lint

Author: leoyvens

Diff for: src/librustc_lint/lib.rs

@@ -294,7 +294,7 @@ pub fn register_builtins(store: &mut lint::LintStore, sess: Option<&Session>) {
         },
         FutureIncompatibleInfo {
             id: LintId::of(WHERE_CLAUSES_OBJECT_SAFETY),
-            reference: "issue TBD",
+            reference: "issue #51443 <https://github.com/rust-lang/rust/issues/51443>",
             edition: None,
         },
         FutureIncompatibleInfo {

Diff for: src/test/ui/issue-50781.stderr

@@ -10,7 +10,7 @@ note: lint level defined here
 LL | #![deny(where_clauses_object_safety)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue TBD
+   = note: for more information, see issue #51443 <https://github.com/rust-lang/rust/issues/51443>
    = note: method `foo` references the `Self` type in where clauses
 
 error: aborting due to previous error