Demote ucd to the secondary benchmarks.

It's very much a stress test, and the crate it's from hasn't been
updated in 5 years.

Author: nnethercote

collector/benchmarks/README.md

@@ -43,9 +43,6 @@ They mostly consist of real-world crates.
   ecosystem.
 - **tokio-webpush-simple**: A simple web server built with tokio. Uses futures
   a lot.
-- **ucd**: A Unicode crate. Contains large statics that
-  [stress](https://github.com/rust-lang/rust/issues/53643) the borrow checker's
-  implementation of NLL.
 - **unicode_normalization**: Unicode character composition and decomposition
   utilities. Uses huge `match` statements that stress the compiler in unusual
   ways.
@@ -112,6 +109,9 @@ compiler in interesting ways.
   with grid coordinates](https://github.com/urschrei/ostn15_phf) that was
   causing rustc to [run out of
   memory](https://github.com/rust-lang/rust/issues/36799).
+- **ucd**: A Unicode crate. Contains large statics that
+  [stress](https://github.com/rust-lang/rust/issues/53643) the borrow checker's
+  implementation of NLL.
 - **unify-linearly**: Contains many variables that all have equality relations
   between them, which caused [exponential
   behavior](https://github.com/rust-lang/rust/pull/32062) in the past.

collector/benchmarks/ucd/perf-config.json

@@ -1,4 +1,4 @@
 {
     "runs": 1,
-    "category": "primary"
+    "category": "secondary"
 }