Error when no subscription count is available

[TemporaryAccount0x1]

• I carefully read the contribution guidelines and agree to them.
• I checked if the issue/feature exists in the latest version.
• I did use the incredible bugreport to markdown converter to paste bug reports.

This issue was first reported by @Brimont in the "Release v0.14.0" issue but it's present in the current stable release v0.13.7 as well. Basically when a channel has no subscription count newpipe will show that some errors occured. I've tested this myself with both v0.13.7 and the latest v0.14.0_rc2 release and both show that there are errors.

How to reproduce ?
Search for "xiaorishu" and then tap on her channel.
This works with other channels too as long as there is no subscription count.

Obligatory stack trace:

Exception

• User Action: requested channel
• Request: https://www.youtube.com/user/xiaorishu
• Content Language: GB
• Service: YouTube
• Version: 0.13.7
• OS: Linux Android 8.0.0 - 26

org.schabi.newpipe.extractor.exceptions.ParsingException: Could not get subscriber count
	at org.schabi.newpipe.extractor.services.youtube.extractors.YoutubeChannelExtractor.getSubscriberCount(YoutubeChannelExtractor.java:138)
	at org.schabi.newpipe.extractor.channel.ChannelInfo.getInfo(ChannelInfo.java:83)
	at org.schabi.newpipe.extractor.channel.ChannelInfo.getInfo(ChannelInfo.java:48)
	at org.schabi.newpipe.util.ExtractorHelper.lambda$getChannelInfo$4$ExtractorHelper(ExtractorHelper.java:121)
	at org.schabi.newpipe.util.ExtractorHelper$$Lambda$4.call(Unknown Source:4)
	at io.reactivex.internal.operators.single.SingleFromCallable.subscribeActual(SingleFromCallable.java:44)
	at io.reactivex.Single.subscribe(Single.java:3310)
	at io.reactivex.internal.operators.single.SingleDoOnSuccess.subscribeActual(SingleDoOnSuccess.java:35)
	at io.reactivex.Single.subscribe(Single.java:3310)
	at io.reactivex.internal.operators.maybe.MaybeFromSingle.subscribeActual(MaybeFromSingle.java:41)
	at io.reactivex.Maybe.subscribe(Maybe.java:4073)
	at io.reactivex.internal.operators.maybe.MaybeConcatArray$ConcatMaybeObserver.drain(MaybeConcatArray.java:153)
	at io.reactivex.internal.operators.maybe.MaybeConcatArray$ConcatMaybeObserver.request(MaybeConcatArray.java:78)
	at io.reactivex.internal.operators.flowable.FlowableElementAtMaybe$ElementAtSubscriber.onSubscribe(FlowableElementAtMaybe.java:66)
	at io.reactivex.internal.operators.maybe.MaybeConcatArray.subscribeActual(MaybeConcatArray.java:42)
	at io.reactivex.Flowable.subscribe(Flowable.java:14349)
	at io.reactivex.internal.operators.flowable.FlowableElementAtMaybe.subscribeActual(FlowableElementAtMaybe.java:36)
	at io.reactivex.Maybe.subscribe(Maybe.java:4073)
	at io.reactivex.internal.operators.maybe.MaybeToSingle.subscribeActual(MaybeToSingle.java:46)
	at io.reactivex.Single.subscribe(Single.java:3310)
	at io.reactivex.internal.operators.single.SingleSubscribeOn$SubscribeOnObserver.run(SingleSubscribeOn.java:89)
	at io.reactivex.Scheduler$DisposeTask.run(Scheduler.java:579)
	at io.reactivex.internal.schedulers.ScheduledRunnable.run(ScheduledRunnable.java:66)
	at io.reactivex.internal.schedulers.ScheduledRunnable.call(ScheduledRunnable.java:57)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:301)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636)
	at java.lang.Thread.run(Thread.java:764)

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[theScrabi]

Will be fixed in v0.14.0