[YouTube] Speed up n parameter presence check

[litetex]

This code does a quick check if the n parameter is even present before running the extraction regex.

The time required to extract an url that does not contain the n-parameter got down from:

• 51200ns to 600ns → ~85x faster

Example: Timings of getThrottlingParameterFromStreamingUrl in ns when running YoutubeStreamExtractorRelatedMixTest:
Before:

[RATE-LIMIT] Waited 0.0s for https://www.youtube.com/youtubei/v1/next?prettyPrint=false
>>101900
>>79800
>>60000
>>58800
>>61200
>>87500
>>61300
>>56000
>>65700
>>71900
>>54700
>>53400
>>67300
>>70700
>>63100
>>70100
>>63800
>>69400
>>60400
>>57800
>>79400
>>85100
>>59000

After:

[RATE-LIMIT] Waited 0.0s for https://www.youtube.com/youtubei/v1/next?prettyPrint=false
>>4200
>>700
>>700
>>600
>>600
>>700
>>600
>>1200
>>900
>>700
>>800
>>800
>>500
>>500
>>600
>>700
>>1100
>>700
>>600
>>600
>>300
>>600
>>800

• I carefully read the contribution guidelines and agree to them.
• I have tested the API against NewPipe.
• I agree to create a pull request for NewPipe as soon as possible to make it compatible with the changed API.

[TobiGr]

Good catch! You might want to add a comment to THROTTLING_PARAM_PATTERN that this check needs to be modified in case the pattern changes.

[litetex]

@TobiGr done :)