Use valid package identifiers in registry loading tests

Author: mattt

Tests/PackageLoadingTests/PD_Next_LoadingTests.swift

@@ -22,21 +22,21 @@ class PackageDescriptionNextLoadingTests: PackageDescriptionLoadingTests {
             let package = Package(
                name: "MyPackage",
                dependencies: [
-                   .package(id: "foo", from: "1.1.1"),
-                   .package(id: "bar", exact: "1.1.1"),
-                   .package(id: "baz", .upToNextMajor(from: "1.1.1")),
-                   .package(id: "qux", .upToNextMinor(from: "1.1.1")),
-                   .package(id: "quux", "1.1.1" ..< "3.0.0"),
+                   .package(id: "x.foo", from: "1.1.1"),
+                   .package(id: "x.bar", exact: "1.1.1"),
+                   .package(id: "x.baz", .upToNextMajor(from: "1.1.1")),
+                   .package(id: "x.qux", .upToNextMinor(from: "1.1.1")),
+                   .package(id: "x.quux", "1.1.1" ..< "3.0.0"),
                ]
             )
             """
         loadManifest(manifest, toolsVersion: self.toolsVersion) { manifest in
         let deps = Dictionary(uniqueKeysWithValues: manifest.dependencies.map{ ($0.identity.description, $0) })
-            XCTAssertEqual(deps["foo"], .registry(identity: "foo", requirement: .range("1.1.1" ..< "2.0.0")))
-            XCTAssertEqual(deps["bar"], .registry(identity: "bar", requirement: .exact("1.1.1")))
-            XCTAssertEqual(deps["baz"], .registry(identity: "baz", requirement: .range("1.1.1" ..< "2.0.0")))
-            XCTAssertEqual(deps["qux"], .registry(identity: "qux", requirement: .range("1.1.1" ..< "1.2.0")))
-            XCTAssertEqual(deps["quux"], .registry(identity: "quux", requirement: .range("1.1.1" ..< "3.0.0")))
+            XCTAssertEqual(deps["x.foo"], .registry(identity: "x.foo", requirement: .range("1.1.1" ..< "2.0.0")))
+            XCTAssertEqual(deps["x.bar"], .registry(identity: "x.bar", requirement: .exact("1.1.1")))
+            XCTAssertEqual(deps["x.baz"], .registry(identity: "x.baz", requirement: .range("1.1.1" ..< "2.0.0")))
+            XCTAssertEqual(deps["x.qux"], .registry(identity: "x.qux", requirement: .range("1.1.1" ..< "1.2.0")))
+            XCTAssertEqual(deps["x.quux"], .registry(identity: "x.quux", requirement: .range("1.1.1" ..< "3.0.0")))
         }
     }
 }