Bug 1990267 - Replace ContentAlpha.medium with a constant value r=android-reviewers,avirvara

The `ContentAlpha.medium` constant from `androidx.compose.material` has been replaced with its literal value `0.6f` in `SearchOverlay.kt`.

Differential Revision: https://phabricator.services.mozilla.com/D265842

Author: mcarare

mobile/android/focus-android/app/lint-baseline.xml

@@ -166,17 +166,6 @@
             column="8"/>
     </issue>
 
-    <issue
-        id="UsingMaterialAndMaterial3Libraries"
-        message="Using a material import while also using the material3 library"
-        errorLine1="import androidx.compose.material.ContentAlpha"
-        errorLine2="       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~">
-        <location
-            file="src/main/java/org/mozilla/focus/searchsuggestions/ui/SearchOverlay.kt"
-            line="10"
-            column="8"/>
-    </issue>
-
     <issue
         id="DataExtractionRules"
         message="The attribute `android:allowBackup` is deprecated from Android 12 and higher and may be removed in future versions. Consider adding the attribute `android:dataExtractionRules` specifying an `@xml` resource which configures cloud backups and device transfers on Android 12 and higher."

mobile/android/focus-android/app/src/main/java/org/mozilla/focus/searchsuggestions/ui/SearchOverlay.kt

@@ -7,7 +7,6 @@ package org.mozilla.focus.searchsuggestions.ui
 import androidx.appcompat.content.res.AppCompatResources
 import androidx.compose.foundation.background
 import androidx.compose.foundation.layout.Column
-import androidx.compose.material.ContentAlpha
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.livedata.observeAsState
 import androidx.compose.runtime.remember
@@ -120,7 +119,7 @@ private fun SearchSuggestions(
                 background = focusColors.surface,
                 title = focusColors.onBackground,
                 description = focusColors.onBackground.copy(
-                    alpha = ContentAlpha.medium,
+                    alpha = 0.6f,
                 ),
                 autocompleteIcon = focusColors.onSurface,
                 groupTitle = focusColors.onBackground,