Remove "this->" from examples

[david-dorf]

Description

"this->" seems to be unnecessary and examples work without it

Did you use Generative AI?

No

[fujitatomoya]

i am not really inclined to take this PR because of the following reasons.

Removing the explicit this-> qualifier inside class methods in C++ can make the code slightly shorter, but is there any other benefits from it?

on the other hand, with this->

• it can be less obvious which variables and methods are members of the class and which are local variables or functions.
• If a method or variable in the same scope has the same name as a class member, removing this-> can lead to unintended shadowing or bugs.
• consistency with other examples in https://github.com/ros2/examples/tree/rolling/rclcpp/topics

if there is no downside to keep this->, i do not think it is worth to replace all of them?

[david-dorf]

This PR would make things less verbose. It's only being removed from rclcpp functions in an intro node for beginners. It is highly unlikely a beginner would encounter a conflict with methods like get_logger()

[david-dorf]

All good, if it's not worth it I'll close

[fujitatomoya]

@david-dorf thanks for sharing thoughts, feel free to reopen this. i think probably we would want to keep the consistency with other samples at least.