Update README.md

[iamshreeram]

Brew installation fails with error Error: Unknown command: cask

Fixes #.

Changes proposed in this pull request:

• Updating the read me from brew cask install graphql-playground to brew install --cask graphql-playground

[linux-foundation-easycla[bot]]

• :x: - Shreeram The commit (837315e24ab5f425bf1de258b951496488cffc18) is not authorized under a signed CLA. Please click here to be authorized. For further assistance with EasyCLA, please submit a support request ticket.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[brianwarner]

@iamshreeram Something is odd here, CLAassistant shouldn't be requiring checks... let me see what's going on here.

[brianwarner]

Ok, you can ignore the CLAassistant comment. I've disabled it for this repo since we use EasyCLA now.

[iamshreeram]

@brianwarner , can you review the PR.

[brianwarner]

I can add a review, but in full transparency I'm only comfortable doing it because it's a pretty trivial change. We're working on a more sustainable plan for long-term maintainership. Looks like you still need to sign the spec membership agreement as well (you'd want to follow the link in the EasyCLA bot's comment).