refactor(environment-variables): adjust ordering logic for environment variables

- Updated the ordering logic in the environment_variables methods for both Application and Service models to prioritize required variables over service-prefixed keys.
- This change enhances the clarity and organization of environment variable retrieval, ensuring that essential variables are listed first.

app/Models/Service.php

@@ -1231,9 +1231,9 @@ class Service extends BaseModel
     {
         return $this->morphMany(EnvironmentVariable::class, 'resourceable')
             ->orderByRaw("
-                CASE 
-                    WHEN LOWER(key) LIKE 'service_%' THEN 1
-                    WHEN is_required = true AND (value IS NULL OR value = '') THEN 2
+                CASE
+                    WHEN is_required = true THEN 1
+                    WHEN LOWER(key) LIKE 'service_%' THEN 2
                     ELSE 3
                 END,
                 LOWER(key) ASC