Fixed bug #1531862: Do not close standard file descriptors in subprocess.

Let's try that once more. Buildbots were broken last time, but probably
because tests were sending data to stderr for testing it (sending to a
file doesn't touch the problem).

The fix is still the same, but tests were reduced (removing tests to
be able to fix something is weird, but oh well).
diff --git a/Misc/NEWS b/Misc/NEWS
index 2cad993..53708c1 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -56,6 +56,8 @@
 
 - Bug #1543303, patch #1543897: remove NUL padding from tarfiles.
 
+- Bug #1531862: Do not close standard file descriptors in subprocess.
+
 
 Extension Modules
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