For #9605: remove unnecessary @RunWith(Robolectric in unit tests.

robolectric increases the run time of tests so it's important to remove
them when they're unnecessary.

Between this change and the last one, the unit test runtime was reduced
by ~10s.

app/src/test/java/org/mozilla/fenix/customtabs/ExternalAppBrowserActivityTest.kt

@@ -14,18 +14,12 @@ import org.junit.Assert.assertEquals
 import org.junit.Assert.assertNotNull
 import org.junit.Assert.assertNull
 import org.junit.Test
-import org.junit.runner.RunWith
 import org.mockito.Mockito.never
 import org.mockito.Mockito.spy
 import org.mockito.Mockito.verify
 import org.mozilla.fenix.BrowserDirection
-import org.mozilla.fenix.TestApplication
 import org.mozilla.fenix.components.metrics.Event
-import org.robolectric.RobolectricTestRunner
-import org.robolectric.annotation.Config
 
-@RunWith(RobolectricTestRunner::class)
-@Config(application = TestApplication::class)
 class ExternalAppBrowserActivityTest {
 
     @Test

app/src/test/java/org/mozilla/fenix/ext/LogTest.kt

@@ -10,13 +10,6 @@ import io.mockk.mockkStatic
 import io.mockk.verify
 import org.junit.Before
 import org.junit.Test
-import org.junit.runner.RunWith
-import org.mozilla.fenix.TestApplication
-import org.robolectric.RobolectricTestRunner
-import org.robolectric.annotation.Config
-
-@RunWith(RobolectricTestRunner::class)
-@Config(application = TestApplication::class)
 
 class LogTest {
 

app/src/test/java/org/mozilla/fenix/ext/NavControllerTest.kt

@@ -15,13 +15,7 @@ import io.mockk.mockk
 import io.mockk.verify
 import org.junit.Before
 import org.junit.Test
-import org.junit.runner.RunWith
-import org.mozilla.fenix.TestApplication
-import org.robolectric.RobolectricTestRunner
-import org.robolectric.annotation.Config
 
-@RunWith(RobolectricTestRunner::class)
-@Config(application = TestApplication::class)
 class NavControllerTest {
 
     private val navController: NavController = mockk(relaxed = true)

app/src/test/java/org/mozilla/fenix/settings/SupportUtilsTest.kt

@@ -11,14 +11,8 @@ import io.mockk.every
 import io.mockk.mockk
 import org.junit.Assert.assertEquals
 import org.junit.Test
-import org.junit.runner.RunWith
-import org.mozilla.fenix.TestApplication
-import org.robolectric.RobolectricTestRunner
-import org.robolectric.annotation.Config
 import java.util.Locale
 
-@RunWith(RobolectricTestRunner::class)
-@Config(application = TestApplication::class)
 class SupportUtilsTest {
 
     @Test