in_type_checking_block can crash if you haven't imported TYPE_CHECKING

[jacobtylerwalls]

Bug description

if TYPE_CHECKING:  # don't import this!
    pass
else:
    import math

Configuration

No response

Command used

pylint a.py

Pylint output

File "/Users/.../pylint/pylint/utils/ast_walker.py", line 96, in walk
    callback(astroid)
  File "/Users/.../pylint/pylint/checkers/variables.py", line 1329, in leave_module
    self._check_imports(not_consumed)
  File "/Users/.../pylint/pylint/checkers/variables.py", line 3071, in _check_imports
    if not in_type_checking_block(stmt):
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/.../pylint/pylint/checkers/utils.py", line 1921, in in_type_checking_block
    maybe_import_from = ancestor.test.lookup(ancestor.test.name)[1][0]
                        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^
IndexError: tuple index out of range

Expected behavior

************* Module a
a.py:1:3: E0602: Undefined variable 'TYPE_CHECKING' (undefined-variable)
a.py:4:4: W0611: Unused import math (unused-import)

Pylint version

pylint 3.0.0a6
astroid 2.16.0dev0
Python 3.11.0

OS / Environment

No response

Additional dependencies

No response