Add icon for sign in

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<vector xmlns:android="http://schemas.android.com/apk/res/android"

        android:width="24.0dp"

        android:height="24.0dp"

        android:viewportWidth="24.0"

        android:viewportHeight="24.0">

    <path

        android:fillColor="#FFFFFFFF"

        android:pathData="M11,7L9.6,8.4l2.6,2.6H2v2h10.2l-2.6,2.6L11,17l5-5L11,7z M20,19h-8v2h8c1.1,0,2-0.9,2-2V5c0-1.1-0.9-2-2-2h-8v2h8V19z"/>

</vector>

                .setButton1Icon(R.drawable.ic_settings_delete)

                .setButton1OnClickListener(view -> forgetNetwork())

                .setButton2Text(R.string.wifi_sign_in_button_text)

                .setButton2Icon(R.drawable.ic_settings_sign_in)

                .setButton2OnClickListener(view -> signIntoNetwork())

                .setButton3Text(R.string.wifi_connect)

                .setButton3Icon(R.drawable.ic_settings_wireless)