internal: add more brokenAuthHeadersProviders

Add log.finalsurge.com and api.medium.com

Fixes #267

Change-Id: I8a902f418f04ff87539fe2edda350a81974aaa6e
Reviewed-on: https://go-review.googlesource.com/92655
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/internal/token.go b/internal/token.go
index e7d078f..7d61117 100644
--- a/internal/token.go
+++ b/internal/token.go
@@ -124,6 +124,8 @@
 	"https://api.patreon.com/",
 	"https://sandbox.codeswholesale.com/oauth/token",
 	"https://api.sipgate.com/v1/authorization/oauth",
+	"https://api.medium.com/v1/tokens",
+	"https://log.finalsurge.com/oauth/token",
 }
 
 // brokenAuthHeaderDomains lists broken providers that issue dynamic endpoints.