Investigate flaky parallel/test-tls-env-extra-ca

[Trott]

This one is new, I think...

https://ci.nodejs.org/job/node-test-commit-arm/18922/nodes=ubuntu1604-arm64/console

00:05:36 not ok 1754 parallel/test-tls-env-extra-ca
00:05:36   ---
00:05:36   duration_ms: 1.671
00:05:36   severity: fail
00:05:36   exitcode: 1
00:05:36   stack: |-
00:05:36     events.js:167
00:05:36           throw er; // Unhandled 'error' event
00:05:36           ^
00:05:36     
00:05:36     Error: 281473004412928:error:1408F119:SSL routines:ssl3_get_record:decryption failed or bad record mac:../deps/openssl/openssl/ssl/record/ssl3_record.c:469:
00:05:36     
00:05:36     Emitted 'error' event at:
00:05:36         at TLSSocket._emitTLSError (_tls_wrap.js:601:10)
00:05:36         at TLSWrap.onerror (_tls_wrap.js:267:11)
00:05:36   ...

@nodejs/crypto