bump tidy's src/test/ui file limit

This commit addresses a tidy error that currently occurs on this branch:

```
tidy error:
    following path contains more than 1458 entries,
    you should move the test to some relevant
    subdirectory (current: 1459): /checkout/src/test/ui
```

Co-authored-by: bjorn3 <bjorn3@users.noreply.github.com>

src/tools/tidy/src/ui_tests.rs

@@ -7,7 +7,7 @@ use std::path::Path;
 
 const ENTRY_LIMIT: usize = 1000;
 // FIXME: The following limits should be reduced eventually.
-const ROOT_ENTRY_LIMIT: usize = 1458;
+const ROOT_ENTRY_LIMIT: usize = 1459;
 const ISSUES_ENTRY_LIMIT: usize = 2669;
 
 fn check_entries(path: &Path, bad: &mut bool) {