Yusuke Endoh b271bd73e0 test/net/smtp/test_smtp.rb: Stop io leaks ... `make test-all` was very noisy by warnings like ``` Leaked file descriptor: Net::TestSMTP#test_start_with_position_argument: 6 : #<TCPSocket:fd 6, AF_INET, 127.0.0.1, 43770> ```		2020-09-26 00:20:06 +09:00
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fixtures	…
ftp	…
http	…
imap	…
pop	…
protocol	…
smtp	test/net/smtp/test_smtp.rb: Stop io leaks	2020-09-26 00:20:06 +09:00