Add 'SwiftLibraryPluginProvider' product

Author: rintaro

Package.swift

@@ -18,6 +18,7 @@ let package = Package(
     .library(name: "SwiftCompilerPluginMessageHandling", targets: ["SwiftCompilerPluginMessageHandling"]),
     .library(name: "SwiftDiagnostics", targets: ["SwiftDiagnostics"]),
     .library(name: "SwiftIDEUtils", targets: ["SwiftIDEUtils"]),
+    .library(name: "SwiftLibraryPluginProvider", targets: ["SwiftLibraryPluginProvider"]),
     .library(name: "SwiftOperators", targets: ["SwiftOperators"]),
     .library(name: "SwiftParser", targets: ["SwiftParser"]),
     .library(name: "SwiftParserDiagnostics", targets: ["SwiftParserDiagnostics"]),