tests: work around broken PyPy globbing by removing inert code

We check to see if a test extension exists, and if so add its path to
sys.path... immediately before unconditionally importing it, obviously.

This raises the question: why bother checking? Can it ever fail? What if
it does fail, do we simply not add path entries and then expect the rest
of the test file to work??? The whole thing seems silly and useless.

In fact it can fail, if the python interpreter and/or standard library
is broken. This is the case for the initial release of PyPy 3.11, in
which `'*tachyon*'` fails to glob correctly (and `'tachyon*'` would
work, funnily enough -- this is valid too for our use case although
still just as pointless).

Delete the useless check. It's technically correct to delete it, and it
*also* works around the PyPy breakage as a bonus.

Closes: https://github.com/mesonbuild/meson/issues/14307
(cherry picked from commit f41c0f5436)

test cases/python/4 custom target depends extmodule/blaster.py

@@ -7,8 +7,7 @@ import argparse
 from pathlib import Path
 
 filedir = Path(os.path.dirname(__file__)).resolve()
-if list(filedir.glob('ext/*tachyon*')):
-    sys.path.insert(0, (filedir / 'ext').as_posix())
+sys.path.insert(0, (filedir / 'ext').as_posix())
 
 if hasattr(os, 'add_dll_directory'):
     os.add_dll_directory(filedir / 'ext' / 'lib')