DEV_PROXY_CERT_PATH silently ignores relative paths and is undocumented #1973

Description

DEV_PROXY_CERT_PATH is ignored without a warning when it contains a relative path. The variable isn't documented.

Code:

• dev-proxy/DevProxy.Proxy.Kestrel/Internal/CertificateAuthority.cs

  Lines 85 to 88 in 43b3724

  	var envPath = Environment.GetEnvironmentVariable("DEV_PROXY_CERT_PATH");
  	var rootPfxPath = !string.IsNullOrEmpty(envPath) && Path.IsPathRooted(envPath)
  	? envPath
  	: Path.Combine(configDirectory, RootCertFileName);

Expected behavior

Relative paths are resolved (or rejected with a warning), and the variable is documented.