Use OrderedCollections so that search results are deterministic

Package.swift

@@ -13,13 +13,18 @@ let package = Package(
     ],
     dependencies: [
         // Dependencies declare other packages that this package depends on.
-        .package(url: "https://github.com/apple/swift-docc-plugin.git", from: "1.3.0")
+        .package(url: "https://github.com/apple/swift-docc-plugin.git", from: "1.3.0"),
+        .package(url: "https://github.com/apple/swift-collections.git", .upToNextMajor(from: "1.1.1"))
     ],
     targets: [
         // Targets are the basic building blocks of a package, defining a module or a test suite.
         // Targets can depend on other targets in this package and products from dependencies.
         .target(
-            name: "SwiftTrie"),
+            name: "SwiftTrie",
+            dependencies: [
+                .product(name: "OrderedCollections", package: "swift-collections")
+            ]
+        ),
         .testTarget(
             name: "SwiftTrieTests",
             dependencies: ["SwiftTrie"])