Minimum iOS version is 13 (#69)

Author: calebkleveter

Package.swift

@@ -4,7 +4,8 @@ import PackageDescription
 let package = Package(
     name: "fluent-sqlite-driver",
     platforms: [
-       .macOS(.v10_15)
+        .macOS(.v10_15),
+        .iOS(.v13)
     ],
     products: [
         .library(name: "FluentSQLiteDriver", targets: ["FluentSQLiteDriver"]),