agent: Verify the source before dereferencing the pointer
The reason is that the component object could have been destroyed in the mean time.
This bug was found the the this CI run: https://gitlab.freedesktop.org/libnice/libnice/-/jobs/9041631
The reason is that the component object could have been destroyed in the mean time.
This bug was found the the this CI run: https://gitlab.freedesktop.org/libnice/libnice/-/jobs/9041631