Properly linkify two doc comment xrefs to issues

Fixes these messages:

warning: this URL is not a hyperlink --> crates/arti/src/watch_cfg.rs:115:5 | 115 | /// https://github.com/notify-rs/notify/issues/165 and | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use an automatic link instead: <https://github.com/notify-rs/notify/issues/165> | = note: #[warn(rustdoc::bare_urls)] on by default = note: bare URLs are not automatically turned into clickable links

warning: this URL is not a hyperlink --> crates/arti/src/watch_cfg.rs:116:5 | 116 | /// https://github.com/notify-rs/notify/pull/166 . | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use an automatic link instead: <https://github.com/notify-rs/notify/pull/166> | = note: bare URLs are not automatically turned into clickable links

crates/arti/src/watch_cfg.rs

@@ -112,8 +112,8 @@ fn reconfigure<R: Runtime>(
 /// making new files and then moving them into place over the old ones.
 ///
 /// For more background on the issues with `notify`, see
-/// https://github.com/notify-rs/notify/issues/165 and
-/// https://github.com/notify-rs/notify/pull/166 .
+/// <https://github.com/notify-rs/notify/issues/165> and
+/// <https://github.com/notify-rs/notify/pull/166>.
 ///
 /// TODO: Someday we might want to make this code exported someplace.  If we do,
 /// we should test it, and improve its API a lot.  Right now, the caller needs