Fix isolation errors in UI tests

Author: rechsteiner

ParchmentUITests/ParchmentUITests.swift

@@ -2,16 +2,15 @@ import XCTest
 
 @MainActor
 final class ParchmentUITests: XCTestCase {
-    var app: XCUIApplication!
-
     override func setUp() {
         continueAfterFailure = false
-        app = XCUIApplication()
-        app.launchArguments = ["--ui-testing"]
-        app.launch()
     }
 
     func testSelect() {
+        let app = XCUIApplication()
+        app.launchArguments = ["--ui-testing"]
+        app.launch()
+
         let cell0 = app.collectionViews.cells["View 0"]
         let cell1 = app.collectionViews.cells["View 1"]
 
@@ -27,6 +26,10 @@ final class ParchmentUITests: XCTestCase {
     }
 
     func testSwipe() {
+        let app = XCUIApplication()
+        app.launchArguments = ["--ui-testing"]
+        app.launch()
+        
         app.scrollViews.firstMatch.swipeLeft()
         let content1 = app.scrollViews.firstMatch.staticTexts["1"]
         XCTAssertTrue(content1.waitForExistence(timeout: 1))