Use com.apple.container.registry as keychain ID. (#652)

- Closes #644.

## Type of Change
- [ ] Bug fix
- [ ] New feature  
- [x] Breaking change
- [ ] Documentation update

## Motivation and Context
Avoids conflicts.

## Testing
- [x] Tested locally
- [ ] Added/updated tests
- [ ] Added/updated docs

Sources/ContainerClient/Core/Constants.swift

@@ -15,5 +15,5 @@
 //===----------------------------------------------------------------------===//
 
 public enum Constants {
-    public static let keychainID = "com.apple.container"
+    public static let keychainID = "com.apple.container.registry"
 }

Sources/Services/ContainerImagesService/Server/ImageService.swift

@@ -26,8 +26,6 @@ import Logging
 import TerminalProgress
 
 public actor ImagesService {
-    public static let keychainID = "com.apple.container"
-
     private let log: Logger
     private let contentStore: ContentStore
     private let imageStore: ImageStore
@@ -165,7 +163,7 @@ extension ImagesService {
         if let authentication {
             return try await body(authentication)
         }
-        let keychain = KeychainHelper(id: Self.keychainID)
+        let keychain = KeychainHelper(id: Constants.keychainID)
         do {
             authentication = try keychain.lookup(domain: host)
         } catch let err as KeychainHelper.Error {