Change package include for swift-syntax

.gitignore

 .build/
 SwiftMetaModelGenerator.xcodeproj/project.xcworkspace/xcuserdata/
 SwiftMetaModelGenerator.xcodeproj/xcuserdata/
+Package.resolved

Package.resolved

-{
-  "pins" : [
-    {
-      "identity" : "pathkit",
-      "kind" : "remoteSourceControl",
-      "location" : "https://github.com/kylef/PathKit.git",
-      "state" : {
-        "revision" : "3bfd2737b700b9a36565a8c94f4ad2b050a5e574",
-        "version" : "1.0.1"
-      }
-    },
-    {
-      "identity" : "spectre",
-      "kind" : "remoteSourceControl",
-      "location" : "https://github.com/kylef/Spectre.git",
-      "state" : {
-        "revision" : "26cc5e9ae0947092c7139ef7ba612e34646086c7",
-        "version" : "0.10.1"
-      }
-    },
-    {
-      "identity" : "stencil",
-      "kind" : "remoteSourceControl",
-      "location" : "https://github.com/kylef/Stencil.git",
-      "state" : {
-        "revision" : "4f222ac85d673f35df29962fc4c36ccfdaf9da5b",
-        "version" : "0.15.1"
-      }
-    },
-    {
-      "identity" : "swift-argument-parser",
-      "kind" : "remoteSourceControl",
-      "location" : "https://github.com/apple/swift-argument-parser.git",
-      "state" : {
-        "revision" : "9f39744e025c7d377987f30b03770805dcb0bcd1",
-        "version" : "1.1.4"
-      }
-    },
-    {
-      "identity" : "swift-syntax",
-      "kind" : "remoteSourceControl",
-      "location" : "https://github.com/apple/swift-syntax.git",
-      "state" : {
-        "revision" : "04d4497be6b88e524a71778d828790e9589ae1c4",
-        "version" : "0.50700.0"
-      }
-    }
-  ],
-  "version" : 2
-}

Package.swift

@@ -10,7 +10,7 @@ let package = Package(
     dependencies: [
         .package(url: "https://github.com/apple/swift-argument-parser.git", exact: "1.1.4"),
         .package(url: "https://github.com/kylef/PathKit.git", exact: "1.0.1"),
-        .package(url: "https://github.com/apple/swift-syntax.git", exact: "0.50700.0"),
+        .package(url: "https://github.com/apple/swift-syntax", branch: "0.50700.0"),
         .package(url: "https://github.com/kylef/Stencil.git", exact: "0.15.1"),
     ],
     targets: [