style: DRY principle for test import

Author: ryan-lempka

lib/llm/src/preprocessor/prompt/template/oai.rs

@@ -330,6 +330,7 @@ impl OAIPromptFormatter for HfTokenizerConfigJsonFormatter {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use minijinja::{context, Environment};
 
     #[test]
     fn test_may_be_fix_tool_schema_missing_type_and_properties() {
@@ -739,8 +740,6 @@ NORMAL MODE
 
     #[test]
     fn test_normalize_tool_arguments_tojson() {
-        use minijinja::{Environment, context};
-
         let tmpl = r#"{{ messages[0].tool_calls[0].function.arguments | tojson }}"#;
 
         // Message with tool_calls containing JSON string arguments
@@ -775,8 +774,6 @@ NORMAL MODE
 
     #[test]
     fn test_normalize_tool_arguments_items_loop() {
-        use minijinja::{Environment, context};
-
         let tmpl = r#"{% for k, v in messages[0].tool_calls[0].function.arguments|items %}{{k}}={{v}};{% endfor %}"#;
 
         let mut messages = serde_json::Value::Array(vec![serde_json::json!({