fix rendering templates created from string literals

Sources/Environment.swift

@@ -43,6 +43,8 @@ public struct Environment {
   }
   
   func render(template: Template, context: [String: Any]?) throws -> String {
+    // update temaplte environment as it cen be created from string literal with default environment
+    template.environment = self
     errorReporter.context = ErrorReporterContext(template: template)
     do {
       return try template.render(context)