Some TLS servers require SNI, but the Golang HTTP client doesn't
include it in the ClientHello when connecting to an IP address. This
change adds a new TLSServerName field to health check definitions to
optionally set it. This fixes#9473.
This commit makes a number of changes that should make
TestLoad_FullConfig easier to work with, and make the test more like
real world scenarios.
* use separate files in testdata/ dir to store the config source.
Separate files are much easier to edit because editors can syntax
highlight json/hcl, and it makes strings easier to find. Previously
trying to find strings would match strings used in other tests.
* use the exported config.Load interface instead of internal NewBuilder
and BuildAndValidate.
* remove the tail config overrides, which are only necessary with
nonZero works.
Freddy