Merge a commit from upstream:
d1cbf6d75280 test/test_ssl_session: skip tests for session_remove_cb
Tests using SSL::SSLContext#session_remove_cb= are now skipped.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@60318 b2dd03c8-39d4-4d8f-98ff-823fe69b080e