Separate authentication tests into new test modules

This MR separates the tests of gwdatafind_server.authentication into their own test modules, so that test_api_v1.py just tests the v1 API (with noauth).

gwdatafind_server/api/base.py

@@ -29,8 +29,8 @@ blueprint = Blueprint(
 # -- version API
 
 @blueprint.route("/version")
-@authentication.validate
 @as_json
+@authentication.validate
 def version():
     supported_apis = current_app.config["supported_apis"]
     return {