Update the youtube link to a working one
Update the youtube link to a working one

The current link leads to a video that is unavailable:

```
Video unavailable
This video contains content from [Merlin] Beggars, who has blocked it on copyright grounds.
```
This new link seems to be the official video that Mr. Beggars would like to promote

```
Licensed to YouTube by
[Merlin] Beggars (on behalf of XL); LatinAutor, UMPG Publishing, CMRRA, SOLAR Music Rights Management, Warner Chappell, Sony ATV Publishing, LatinAutor - SonyATV, UBEM, and 9 Music Rights Societies
```
thoughtbot/high_voltage,thoughtbot/high_voltage