Remove incorrect tests and reenable some of the non-flaky ones (#3653)

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Task/Issue URL:
https://app.asana.com/0/856498667320406/1208838718874817/f
- https://app.asana.com/0/856498667320406/1208796111998084/f

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**Description**:

Remove incorrect tests and reenable some of the non-flaky ones

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**Steps to test this PR**:

Check the Ci.

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**Definition of Done (Internal Only)**:

* [ ] Does this PR satisfy our [Definition of
Done](https://app.asana.com/0/1202500774821704/1207634633537039/f)?

---
###### Internal references:
[Software Engineering
Expectations](https://app.asana.com/0/59792373528535/199064865822552)
[Technical Design
Template](https://app.asana.com/0/59792373528535/184709971311943)

DuckDuckGo.xcodeproj/project.pbxproj

@@ -982,7 +982,6 @@
 		CBAA195A27BFE15600A4BD49 /* NSManagedObjectContextExtension.swift in Sources */ = {isa = PBXBuildFile; fileRef = CBAA195927BFE15600A4BD49 /* NSManagedObjectContextExtension.swift */; };
 		CBC83E3429B631780008E19C /* Configuration in Frameworks */ = {isa = PBXBuildFile; productRef = CBC83E3329B631780008E19C /* Configuration */; };
 		CBC88EE12C7F834300F0F8C5 /* SpecialErrorPageUserScriptTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = CBC88EE02C7F834300F0F8C5 /* SpecialErrorPageUserScriptTests.swift */; };
-		CBC88EE32C7F8B1700F0F8C5 /* SpecialErrorPageTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = CBC88EE22C7F8B1700F0F8C5 /* SpecialErrorPageTests.swift */; };
 		CBC88EE52C8097B500F0F8C5 /* URLCredentialCreator.swift in Sources */ = {isa = PBXBuildFile; fileRef = CBC88EE42C8097B500F0F8C5 /* URLCredentialCreator.swift */; };
 		CBCCF96828885DEE006F4A71 /* AppPrivacyConfigurationTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 02C4BC3127C3F9B600C40026 /* AppPrivacyConfigurationTests.swift */; };
 		CBD4F13C279EBF4A00B20FD7 /* HomeMessage.swift in Sources */ = {isa = PBXBuildFile; fileRef = CBD4F13B279EBF4A00B20FD7 /* HomeMessage.swift */; };
@@ -2817,7 +2816,6 @@
 		CBB6B2542AF6D543006B777C /* lt */ = {isa = PBXFileReference; lastKnownFileType = text.plist.strings; name = lt; path = lt.lproj/InfoPlist.strings; sourceTree = "<group>"; };
 		CBC7AB542AF6D583008CB798 /* ro */ = {isa = PBXFileReference; lastKnownFileType = text.plist.strings; name = ro; path = ro.lproj/InfoPlist.strings; sourceTree = "<group>"; };
 		CBC88EE02C7F834300F0F8C5 /* SpecialErrorPageUserScriptTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SpecialErrorPageUserScriptTests.swift; sourceTree = "<group>"; };
-		CBC88EE22C7F8B1700F0F8C5 /* SpecialErrorPageTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SpecialErrorPageTests.swift; sourceTree = "<group>"; };
 		CBC88EE42C8097B500F0F8C5 /* URLCredentialCreator.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = URLCredentialCreator.swift; sourceTree = "<group>"; };
 		CBC8DC252AF6D4CD00BA681A /* da */ = {isa = PBXFileReference; lastKnownFileType = text.plist.strings; name = da; path = da.lproj/InfoPlist.strings; sourceTree = "<group>"; };
 		CBD4F13B279EBF4A00B20FD7 /* HomeMessage.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = HomeMessage.swift; sourceTree = "<group>"; };
@@ -6001,7 +5999,6 @@
 				F189AED61F18F6DE001EBAE1 /* TabTests.swift */,
 				D625AAEA2BBEEFC900BC189A /* TabURLInterceptorTests.swift */,
 				CBC88EE02C7F834300F0F8C5 /* SpecialErrorPageUserScriptTests.swift */,
-				CBC88EE22C7F8B1700F0F8C5 /* SpecialErrorPageTests.swift */,
 			);
 			name = Tabs;
 			sourceTree = "<group>";
@@ -8157,7 +8154,6 @@
 				CBDD5DE129A6741300832877 /* MockBundle.swift in Sources */,
 				C158AC7B297AB5DC0008723A /* MockSecureVault.swift in Sources */,
 				569437342BE4E41500C0881B /* SyncErrorHandlerSyncErrorsAlertsTests.swift in Sources */,
-				CBC88EE32C7F8B1700F0F8C5 /* SpecialErrorPageTests.swift in Sources */,
 				85C11E4120904BBE00BFFEB4 /* VariantManagerTests.swift in Sources */,
 				F1134ECE1F40EA9C00B73467 /* AtbParserTests.swift in Sources */,
 				F189AEE41F18FDAF001EBAE1 /* LinkTests.swift in Sources */,

DuckDuckGoTests/MockTabDelegate.swift

@@ -115,6 +115,14 @@ final class MockTabDelegate: TabDelegate {
 
 }
 
+final class MockCredentialCreator: URLCredentialCreating {
+
+    func urlCredentialFrom(trust: SecTrust?) -> URLCredential? {
+        return URLCredential(user: "", password: "", persistence: .forSession)
+    }
+
+}
+
 extension TabViewController {
 
     static func fake(

DuckDuckGoTests/PixelTests.swift

@@ -30,7 +30,6 @@ class PixelTests: XCTestCase {
     let userAgentName = "User-Agent"
 
     override func setUpWithError() throws {
-        throw XCTSkip("Potentially flaky")
         try super.setUpWithError()
 
         Pixel.isDryRun = false
@@ -162,7 +161,8 @@ class PixelTests: XCTestCase {
         wait(for: [expectation], timeout: 5.0)
     }
 
-    func testPixelDebouncePreventsFiringWithinInterval() {
+    func testPixelDebouncePreventsFiringWithinInterval() throws {
+        throw XCTSkip("Flaky")
         let firstFireExpectation = XCTestExpectation(description: "First pixel fire should succeed")
         let thirdFireExpectation = XCTestExpectation(description: "Third pixel fire should succeed after debounce interval")