HANDSHAKE_SSL_ERROR with RDS using node 12

[bjornstar]

When using "Amazon RDS" as SSL config we get the following error:

{
  library: 'SSL routines',
  function: 'ssl_choose_client_version',
  reason: 'unsupported protocol',
  code: 'HANDSHAKE_SSL_ERROR',
  fatal: true
}

Error: 4486972864:error:1425F102:SSL routines:ssl_choose_client_version:unsupported protocol:../deps/openssl/openssl/ssl/statem/statem_lib.c:1922

Same configuration works fine under node 11 and node 10.

[bjornstar]

Digging into this, it looks like our RDS instances (mysql v5.6) do not support TLSv1.2, we will have to migrate to mysql v5.7 in order to update to node v12.

In the meantime I have created a PR with node v12 as a test target and fixed a broken test there -- #2211