Refactor FXIOS-12796 [Swift 6 Migration] Fix strict concurrency warnings in unit tests for Sync and some of Storage (#30991)

* Fix Sync target unit test strict concurrency errors.

* Fix DiskImageStoreTests and RustLoginsTests in Storage target unit test strict concurrency errors.

Author: ih-codes

firefox-ios/firefox-ios-tests/Tests/StorageTests/DiskImageStoreTests.swift

@@ -7,16 +7,15 @@ import Shared
 import UIKit
 import XCTest
 
+@MainActor
 class DiskImageStoreTests: XCTestCase {
-    var files: FileAccessor!
     var store: DiskImageStore!
 
-    override func setUp() {
-        super.setUp()
-        files = MockFiles()
-        store = DefaultDiskImageStore(files: files, namespace: "DiskImageStoreTests", quality: 1)
+    override func setUp() async throws {
+        try await super.setUp()
+        store = DefaultDiskImageStore(files: MockFiles(), namespace: "DiskImageStoreTests", quality: 1)
 
-        clearStore()
+        await clearStore()
     }
 
     func testSaveImageForKey() async throws {
@@ -56,12 +55,10 @@ class DiskImageStoreTests: XCTestCase {
         }
     }
 
-// MARK: - Helper methods
+    // MARK: - Helper methods
 
-    func clearStore() {
-        Task {
-            try? await store?.clearAllScreenshotsExcluding(Set())
-        }
+    func clearStore() async {
+        try? await store?.clearAllScreenshotsExcluding(Set())
     }
 
     func makeImageWithColor(_ color: UIColor, size: CGSize) -> UIImage {

firefox-ios/firefox-ios-tests/Tests/StorageTests/RustLoginsTests.swift

@@ -8,7 +8,8 @@ import XCTest
 
 @testable import Storage
 
-class RustLoginsTests: XCTestCase {
+// FIXME: FXIOS-14312 Class is not thread safe
+class RustLoginsTests: XCTestCase, @unchecked Sendable {
     var files: FileAccessor!
     var logins: RustLogins!
     let login = LoginEntry(fromJSONDict: [

firefox-ios/firefox-ios-tests/Tests/SyncTests/RustSyncManagerAPITests.swift

@@ -27,6 +27,6 @@ class RustSyncManagerAPITests: XCTestCase {
                 expectation.fulfill()
             }
 
-        waitForExpectations(timeout: 5)
+        wait(for: [expectation], timeout: 5)
     }
 }