[DRE-maint] Bug#919516: ruby2.5 ftbfs in testing/unstable: certificate verify failed (certificate has expired)

[Matthias Klose]

Package: src:ruby2.5
Version: 2.5.3-3
Severity: serious
Tags: sid buster

[...]
 13) Error:
TestNetHTTPS#test_get:
OpenSSL::SSL::SSLError: SSL_connect returned=1 errno=0 state=error: certificate
verify failed (certificate has expired)
    /home/packages/tmp/ruby2.5-2.5.3/lib/net/protocol.rb:44:in `connect_nonblock'
    /home/packages/tmp/ruby2.5-2.5.3/lib/net/protocol.rb:44:in `ssl_socket_connect'
    /home/packages/tmp/ruby2.5-2.5.3/lib/net/http.rb:981:in `connect'
    /home/packages/tmp/ruby2.5-2.5.3/lib/net/http.rb:920:in `do_start'
    /home/packages/tmp/ruby2.5-2.5.3/lib/net/http.rb:909:in `start'
    /home/packages/tmp/ruby2.5-2.5.3/lib/net/http.rb:1455:in `request'
    /home/packages/tmp/ruby2.5-2.5.3/lib/net/http.rb:1365:in `request_get'
    /home/packages/tmp/ruby2.5-2.5.3/test/net/http/test_https.rb:44:in `test_get'

 14) Error:
TestNetHTTPS#test_post:
OpenSSL::SSL::SSLError: SSL_connect returned=1 errno=0 state=error: certificate
verify failed (certificate has expired)
    /home/packages/tmp/ruby2.5-2.5.3/lib/net/protocol.rb:44:in `connect_nonblock'
    /home/packages/tmp/ruby2.5-2.5.3/lib/net/protocol.rb:44:in `ssl_socket_connect'
    /home/packages/tmp/ruby2.5-2.5.3/lib/net/http.rb:981:in `connect'
    /home/packages/tmp/ruby2.5-2.5.3/lib/net/http.rb:920:in `do_start'
    /home/packages/tmp/ruby2.5-2.5.3/lib/net/http.rb:909:in `start'
    /home/packages/tmp/ruby2.5-2.5.3/lib/net/http.rb:1455:in `request'
    /home/packages/tmp/ruby2.5-2.5.3/lib/net/http.rb:1409:in `request_post'
    /home/packages/tmp/ruby2.5-2.5.3/test/net/http/test_https.rb:58:in `test_post'

Finished tests in 289.841475s, 59.8914 tests/s, 7810.6041 assertions/s.
17359 tests, 2263837 assertions, 5 failures, 9 errors, 19 skips

ruby -v: ruby 2.5.3p105 (2018-10-18 revision 65156) [x86_64-linux-gnu]
make[2]: *** [uncommon.mk:698: yes-test-almost] Error 14
make[2]: Leaving directory '/home/packages/tmp/ruby2.5-2.5.3'
make[1]: *** [debian/rules:81: override_dh_auto_test-arch] Error 2
make[1]: Leaving directory '/home/packages/tmp/ruby2.5-2.5.3'
make: *** [debian/rules:59: build] Error 2