fix: minor changes to allow for refdoc regeneration (#600)

Author: bshaffer

.repo-metadata.json

@@ -0,0 +1,7 @@
+{
+    "language": "php",
+    "distribution_name": "google/auth",
+    "release_level": "stable",
+    "client_documentation": "https://cloud.google.com/php/docs/reference/auth/latest",
+    "library_type": "CORE"
+}

composer.json

@@ -3,7 +3,7 @@
   "type": "library",
   "description": "Google Auth Library for PHP",
   "keywords": ["google", "oauth2", "authentication"],
-  "homepage": "http://github.com/google/google-auth-library-php",
+  "homepage": "https://github.com/google/google-auth-library-php",
   "license": "Apache-2.0",
   "support": {
     "docs": "https://googleapis.github.io/google-auth-library-php/main/"