Issue #10512: close the log file in cgi when running tests.

Thanks to Nadeem Vawda for the find and an initial fix.

Lib/test/test_cgi.py

@@ -155,6 +155,7 @@ def test_log(self):
             cgi.logfp = None
             cgi.logfile = "/dev/null"
             cgi.initlog("%s", "Testing log 3")
+            self.addCleanup(cgi.logfp.close)
             cgi.log("Testing log 4")
 
     def test_fieldstorage_readline(self):

Misc/NEWS

@@ -54,6 +54,8 @@ Build
 Tests
 -----
 
+- Issue #10512: Properly close sockets under test.test_cgi.
+
 - Issue #10992: Make tests pass under coverage.
 
 - Issue #10826: Prevent sporadic failure in test_subprocess on Solaris due