fix expired goals capacity of action server

[spiralray]

fix #926

This fix is important for action server nodes especially on Windows.

[spiralray]

PROBLEM

If more than one goals received, buffer-overflow occurs at the variable rcl_action_expire_goals when some messages get expired.

DETAILS

The method rcl_action_expire_goals checks whether action goals are expired, and expired goals are copied to the buffer expired_goals.
The parameter expired_goals_capacity shows the size of the buffer expired_goals.

At line 605, variable i indicates the current for-loop index of the goal_handle which is checked expired or not.
And variable 'i' is decerment when the targeted goal_handle is expired and deleted from the array action_server->impl->goal_handles.

So, if expired_goals_capacity equals one and action_server->impl->goal_handles[0] get expired, buffer overflow will occur.

よろしくお願いします。

[fujitatomoya]

lgtm

[fujitatomoya]

https://build.ros2.org/job/Rpr__rcl__ubuntu_focal_amd64/579/ are unrelated to the fix.

@ros-pull-request-builder retest this please

[clalancette]

CI:

• Linux
• Linux-aarch64
• macOS
• Windows

[KavenYau]

@fujitatomoya @clalancette Would this be backported to foxy?

[fujitatomoya]

@Mergifyio backport foxy galactic

[mergify]

backport foxy galactic

✅ Backports have been created

• #957 fix expired goals capacity of action server (backport #931) has been created for branch foxy
• #958 fix expired goals capacity of action server (backport #931) has been created for branch galactic