test: Split spec tests into multiple subfolders

Signed-off-by: Wolfgang Walther <walther@technowledgy.de>

test/spec/Feature/OpenApi/ProxySpec.hs

@@ -0,0 +1,13 @@
+module Feature.OpenApi.ProxySpec where
+
+import Network.Wai (Application)
+import Test.Hspec  hiding (pendingWith)
+
+import Protolude
+import SpecHelper
+
+spec :: SpecWith ((), Application)
+spec =
+  describe "GET / with proxy" $
+    it "returns a valid openapi spec with proxy" $
+      validateOpenApiResponse [("Accept", "application/openapi+json")]