fix: Make UI tests handle hyperlinks consistently (#15640)

In #15639, @weihanglo noted that one of the lint tests passed in CI, but
locally it would fail as it had a hyperlink added to its output. The
root cause appears to be the recent update to `anstyle-svg@0.1.8`, which
added support for hyperlinks, combined with our hyperlink support
autodetection, disabling them in CI, but allowing them locally. To
ensure we are consistently handling hyperlinks, I made them always
enabled for UI tests. This seemed like the best option given that we
already force colors for UI tests, and it allows us to test our
hyperlink output.

Author: weihanglo

crates/cargo-test-support/src/lib.rs

@@ -1505,6 +1505,7 @@ impl CargoCommandExt for snapbox::cmd::Command {
         Self::new(cargo_exe())
             .with_assert(compare::assert_ui())
             .env("CARGO_TERM_COLOR", "always")
+            .env("CARGO_TERM_HYPERLINKS", "true")
             .test_env()
     }
 }