don't require shared_preload_libraries in spec in local tests -

we don't pass settings this way in local setup

compute_tools/src/config.rs

@@ -174,13 +174,24 @@ pub fn write_postgres_conf(
     // pgaudit extension creates event triggers that require library to be loaded.
     // so, once extension was installed it must always be present in shared_preload_libraries.
     let mut extra_shared_preload_libraries = String::new();
-    let libs = spec
-        .cluster
-        .settings
-        .find("shared_preload_libraries")
-        .expect("shared_preload_libraries setting is missing in the spec");
-    // We don't distribute pgaudit in the testing image,
-    // so disable this logic there.
+
+    let libs = {
+        // We don't distribute pgaudit in the testing image,
+        // and don't pass shared_preload_libraries via spec,
+        // so disable this logic there.
+        #[cfg(feature = "testing")]
+        {
+            String::new()
+        }
+        #[cfg(not(feature = "testing"))]
+        {
+            spec.cluster
+                .settings
+                .find("shared_preload_libraries")
+                .expect("shared_preload_libraries setting is missing in the spec")
+        }
+    };
+
     #[cfg(not(feature = "testing"))]
     if !libs.contains("pgaudit") {
         extra_shared_preload_libraries.push_str(",pgaudit");