The default value for ssl.supported_protocols no longer includes TLSv1
as this is an old protocol with known security issues.
Administrators can enable TLSv1.0 support by configuring the
appropriate `ssl.supported_protocols` setting, for example:
xpack.security.http.ssl.supported_protocols: ["TLSv1.2","TLSv1.1","TLSv1"]
Relates: #36021
This introduces a new ssl-config library that can parse
and validate SSL/TLS settings and files.
It supports the standard configuration settings as used in the
Elastic Stack such as "ssl.verification_mode" and
"ssl.certificate_authorities" as well as all file formats used
in other parts of Elasticsearch security (such as PEM, JKS,
PKCS#12, PKCS#8, et al).
Tim Vernum