test(ffe): skip slow miri tests (#1295)

test(ffe): skip slow miri tests

These tests mostly read and deserialize JSON file, which mostly
exercises file IO and serde—not very helpful but takes surprisingly
long to run under miri.

Co-authored-by: oleksii.shmalko <oleksii.shmalko@datadoghq.com>

Author: dd-oleksii

datadog-ffe/build.rs

@@ -121,6 +121,11 @@ fn main() {
         let test_name = format!("evaluation_sdk_{}", test_file.replace('-', "_"));
 
         writeln!(file, "#[test]").unwrap();
+        writeln!(
+            file,
+            "#[cfg_attr(miri, ignore)] // these tests are way too slow on miri"
+        )
+        .unwrap();
         writeln!(file, "fn {}() {{", test_name).unwrap();
         writeln!(
             file,

datadog-ffe/src/rules_based/ufc/models.rs

@@ -508,6 +508,7 @@ mod tests {
     use super::{TryParse, UniversalFlagConfigWire};
 
     #[test]
+    #[cfg_attr(miri, ignore)] // this test is way too slow on miri
     fn parse_flags_v1() {
         let json_content = {
             let path = if std::path::Path::new("tests/data/flags-v1.json").exists() {