Fix getting started instructions for typescript

[jackhughesweb]

Some exercise README templates contain links to pages which no longer exist in v2 Exercism.

For example, C++'s README template had a link to /languages/cpp for instructions on running tests. The correct URLs to use can be found in the 'Still stuck?' sidebar of exercise pages on the live site. You'll need to join the track and go to the first exercise to see them.

Please update any broken links in the 'config/exercise_readme.go.tmpl' file, and run 'configlet generate .' to generate new exercise READMEs with the fixes.

Instructions for generating READMEs with configlet can be found at:
https://github.com/exercism/docs/blob/master/language-tracks/exercises/anatomy/readmes.md#generating-a-readme

Instructions for installing configlet can be found at:
https://github.com/exercism/docs/blob/bc29a1884da6c401de6f3f211d03aabe53894318/language-tracks/launch/first-exercise.md#the-configlet-tool

Tracking exercism/exercism#4102

[YashdalfTheGray]

I can try and give this a shot over the next couple of nights!

[YashdalfTheGray]

@jackhughesweb @masters3d

There actually seems to be only one link in the .tmpl file and it points to the right thing. I'm not sure what else is needed but I'm happy to investigate further if you think something else needs to be checked.