Update from Hummingbird Project Template (#58)

* Update from hummingbird-project-template 572d468b2cabeca286314c5a35196bd42445c8ef

* run swift-format

* Remove .swiftformat

---------

Co-authored-by: adam-fowler <adam-fowler@users.noreply.github.com>
Co-authored-by: Adam Fowler <adamfowler71@gmail.com>

Sources/Mustache/Lambda.swift

@@ -50,6 +50,6 @@ public struct MustacheLambda {
     }
 
     internal func callAsFunction(_ s: String) -> Any? {
-        return self.callback(s)
+        self.callback(s)
     }
 }