pytest-instafail is not needed to run tests.

--- psutil-7.1.3/setup.py.orig
+++ psutil-7.1.3/setup.py
@@ -78,7 +78,6 @@
 # `make install-pydeps-test`.
 TEST_DEPS = [
     "pytest",
-    "pytest-instafail",
     "pytest-subtests",
     "pytest-xdist",
     "setuptools",