Should we handle SSL_CERT_DIR in loadPool()?

The following discussion from !291 (merged) should be addressed:

• @jaime started a discussion:

  question: do you think that !125 (closed) will still be needed? If so, can you create a follow-up issue and point to the issue in this TODO? Otherwise, we can remove this and close !125 (closed)

See these discussions:

• !125 (comment 129422405)
• !291 (comment 348874703)

TestAccessControlWithSSLCertDir fails on macOS since the SSL_CERT_DIR is not loaded

From the Go source code, SSL_CERT_FILE and SSL_CERT_DIR are not loaded on GOOS=darwin (see the build tags of root_unix.go), so we need to do load them manually in Pages, at least for local development and testing.