cibuildwheel: removing unused selector pp*

See this build warning:

    Warning: cibuildwheel: Invalid skip selector: 'pp*'. This selector matches a group that wasn't enabled. Enable it using the `enable` option or remove this selector. This selector will have no effect.

Author: vlaci

pyproject.toml

@@ -2,7 +2,7 @@
 # skip testing in the cibuildwheel phase, will install the wheels later
 # and verify
 test-command = ""
-skip = ["pp*", "*musl*",  "*-manylinux_i686", "*win32"]
+skip = ["*musl*",  "*-manylinux_i686", "*win32"]
 
 [tool.cibuildwheel.macos.environment]
 MACOSX_DEPLOYMENT_TARGET = "10.12"