Remove ipdb import in tumctf2016_zwiebel example

[github-actions[bot]]

Unit Test Results

10 files  ±  0  10 suites  ±0   9m 6s :stopwatch: - 40m 27s 80 tests  - 13  80 :heavy_check_mark:  - 6  0 :zzz: ±0  0 :x:  - 1 

Results for commit c0782f73. ± Comparison against base commit 4123e49d.

This pull request removes 13 tests.

``` test_examples ‑ test_0ctf_momo_3 test_examples ‑ test_CADET_00001 test_examples ‑ test_asisctffinals2015_fake test_examples ‑ test_b01lersctf test_examples ‑ test_cmu_binary_bomb test_examples ‑ test_csaw_wyvern test_examples ‑ test_defcon2019quals_veryandroidoso test_examples ‑ test_flareon2015_5 test_examples ‑ test_hitcon2017_sakura test_examples ‑ test_mbrainfuzz … ```

:recycle: This comment has been updated with latest results.