Fix: Disabled tab switcher menu button (#6719)

Task/Issue URL:
https://app.asana.com/1/137249556945/project/414730916066338/task/1211198220567356?focus=true

### Description

This PR fixes the issue when the toolbar menu button was disabled when
there is just a single NTP tab.

### Steps to test this PR

- [x] Make sure there is just a single NTP tab open
- [x] Open the tab switcher
- [x] Verify the `...` button is enabled
- [x] Tap on it and verify all menu items are functional

Author: 0nko

app/src/main/java/com/duckduckgo/app/tabs/ui/TabSwitcherViewModel.kt

@@ -671,7 +671,6 @@ class TabSwitcherViewModel @Inject constructor(
 
         val dynamicInterface = when (mode) {
             is Normal -> {
-                val isThereOnlyNewTabPage = tabs.size == 1 && tabs.first().isNewTabPage
                 DynamicInterface(
                     isFireButtonVisible = true,
                     isNewTabButtonVisible = isNewToolbarEnabled,
@@ -688,7 +687,7 @@ class TabSwitcherViewModel @Inject constructor(
                     isCloseOtherTabsVisible = false,
                     isCloseAllTabsDividerVisible = true,
                     isCloseAllTabsVisible = true,
-                    isMenuButtonEnabled = !isThereOnlyNewTabPage,
+                    isMenuButtonEnabled = true,
                     isMainFabVisible = !isNewToolbarEnabled,
                     isAIFabVisible = isDuckAIButtonVisible && !isNewToolbarEnabled,
                     mainFabType = FabType.NEW_TAB,

app/src/test/java/com/duckduckgo/app/tabs/ui/TabSwitcherViewModelTest.kt

@@ -920,7 +920,7 @@ class TabSwitcherViewModelTest {
             isCloseOtherTabsVisible = false,
             isCloseAllTabsDividerVisible = true,
             isCloseAllTabsVisible = true,
-            isMenuButtonEnabled = false,
+            isMenuButtonEnabled = true,
             isMainFabVisible = true,
             isAIFabVisible = true,
             mainFabType = FabType.NEW_TAB,
@@ -1341,7 +1341,7 @@ class TabSwitcherViewModelTest {
             isCloseOtherTabsVisible = false,
             isCloseAllTabsDividerVisible = true,
             isCloseAllTabsVisible = true,
-            isMenuButtonEnabled = false,
+            isMenuButtonEnabled = true,
             isMainFabVisible = false,
             isAIFabVisible = false,
             mainFabType = FabType.NEW_TAB,