A fix needed to a link in "HelloWorld" tutorial

[Madejski]

The link in the 3rd line of the HelloWorld tutorial's "Setup" section is broken, needs fixing, for the newbies to be able to move forward. I think the correct one is at https://github.com/LSSTScienceCollaborations/StackClub/blob/e5d2423eacc033e8ba9d54842352343d65cd3395/GettingStarted/GettingStarted.md but there appears to be a pull request - see #121 - @Madejski

[kadrlica]

@Madejski just checking on this issue. Have you been able to fix the url?