Recorder: remove redundant activity label

<?xml version="1.0" encoding="utf-8"?>

<!-- Copyright (c) 2017-2021 The LineageOS Project

<!-- Copyright (c) 2017-2022 The LineageOS Project

     Licensed under the Apache License, Version 2.0 (the "License");

     you may not use this file except in compliance with the License.

        <activity

            android:name=".RecorderActivity"

            android:exported="true"

            android:label="@string/app_name"

            android:theme="@style/AppTheme.Main">

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />