Fix #4135: Remove leftover TODO (#5321)

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Fix #4135: The only thing left is removing the TODO comment, as the
tests were created in #5224

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Co-authored-by: Adhiambo Peres <59600948+adhiamboperes@users.noreply.github.com>

app/src/main/java/org/oppia/android/app/customview/interaction/FractionInputInteractionView.kt

@@ -20,8 +20,6 @@ import org.oppia.android.app.utility.KeyboardHelper.Companion.showSoftKeyboard
 //  background="@drawable/edit_text_background"
 //  maxLength="200".
 
-// TODO(#4135): Add a dedicated test suite for this class.
-
 /** The custom EditText class for fraction input interaction view. */
 class FractionInputInteractionView @JvmOverloads constructor(
   context: Context,