`test_examples.test_mbrainfuzz` is failing in CI

[twizmwazin]

Description

Traceback (most recent call last):
  File "/__w/angr-doc/angr-doc/build/src/angr-doc/tests/test_examples.py", line 222, in test_mbrainfuzz
    exampletest_single("secuinside2016mbrainfuzz") # 1m46s
  File "/__w/angr-doc/angr-doc/build/src/angr-doc/tests/test_examples.py", line 32, in exampletest_single
    module.test()
  File "/__w/angr-doc/angr-doc/build/src/angr-doc/examples/secuinside2016mbrainfuzz/solve.py", line 144, in test
    p = main(b)
  File "/__w/angr-doc/angr-doc/build/src/angr-doc/examples/secuinside2016mbrainfuzz/solve.py", line 133, in main
    (to_find, to_avoid, byte_addresses) = static_analyses(p)
  File "/__w/angr-doc/angr-doc/build/src/angr-doc/examples/secuinside2016mbrainfuzz/solve.py", line 54, in static_analyses
    avoid = function.get_call_return(calling_block_addr) + 3
TypeError: unsupported operand type(s) for +: 'NoneType' and 'int'

Steps to reproduce the bug

Run CI

Environment

CI

Additional context

No response