Skipcargo dev generate-all test case in CI (#14972)

This means that CI tests fail in a way that is redundant with the
dedicated CI job which can obscure signal on whether actual tests are
failing

e.g.,
4703411653

crates/uv-dev/src/generate_options_reference.rs

@@ -402,6 +402,11 @@ mod tests {
 
     #[test]
     fn test_generate_options_reference() -> Result<()> {
+        // Skip this test in CI to avoid redundancy with the dedicated CI job
+        if env::var_os(EnvVars::CI).is_some() {
+            return Ok(());
+        }
+
         let mode = if env::var(EnvVars::UV_UPDATE_SCHEMA).as_deref() == Ok("1") {
             Mode::Write
         } else {