Fixes #2311 : print the fully qualified class names.

[chaehwanli]

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• PR should be motivated, i.e. what does it fix, why, and if relevant how
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-. replace getName() with getSimpleName()

[TimvdLippe]

We no longer use the release/3.x branch, so #2320 suffices for now. I think I will have a chance tomorrow to review the PR.

[chaehwanli]

I'm just showing that I'm a complete beginner.
Using the release branch for PR... I'm sorry for wasting your time.

[TimvdLippe]

Don't worry about it, our branch naming was confusing! It's an easy mistake to make, so no worries at all 😄

[chaehwanli]

thank you~ :)