Update lastest guidance

Signed-off-by: Tran Ngoc Nhan <[email protected]>

Author: ngocnhan-tran1996

CONTRIBUTING.adoc

@@ -81,6 +81,9 @@ The wiki pages https://github.com/spring-projects/spring-framework/wiki/Code-Sty
 
 To format the code as well as check the style, run `./gradlew format && ./gradlew check`.
 
+NOTE: Since the Stream API is https://github.com/spring-projects/spring-security/issues/7154[much slower] than `for` loop, please use it judiciously.
+The team may ask you to change it to a `for` loop if the given code is along a hot path.
+
 [[submit-a-pull-request]]
 === Submit a Pull Request
 

docs/modules/ROOT/pages/community.adoc

@@ -21,7 +21,8 @@ We welcome your involvement in the Spring Security project.
 There are many ways to contribute, including answering questions on Stack Overflow, writing new code, improving existing code, assisting with documentation, developing samples or tutorials, reporting bugs, or simply making suggestions.
 For more information, see our https://github.com/spring-projects/spring-security/blob/main/CONTRIBUTING.adoc[Contributing] documentation.
 
-NOTE: Avoid usage of the Stream API for performance reasons. See https://github.com/spring-projects/spring-security/issues/7154[Spring Issue #7154] for more details.
+NOTE: Since the Stream API is https://github.com/spring-projects/spring-security/issues/7154[much slower] than `for` loop, please use it judiciously.
+The team may ask you to change it to a `for` loop if the given code is along a hot path.
 
 [[community-source]]
 == Source Code