Command highlighting and possible incorrect command in CONTRIBUTING.md

[TylerSanford]

Description

Line 44 of CONTRIBUTING.md the command is not highlighting git clone which is a part of the command block.

Also the command git clone git@github.com:<your-username>/gatsby.git doesn't work for me.

Proposed new command line of git clone https://github.com/<your-username>/gatsby.git which does work for me every time.

Steps to reproduce

By viewing the doc CONTRIBUTING.md line 44, also by attempting the command as described: git clone git@github.com:<your-username>/gatsby.git

Expected result

Docs should have the whole command highlighted to eliminate confusion. Also command should properly clone the fork.

Actual result

`tsanford@Tylers-MacBook-Pro.local:~/Desktop$ git clone git@github.com:tylersanford/hello-world.git
Cloning into 'hello-world'...
git@github.com: Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.`

Environment

• Gatsby version (npm list gatsby): N/A - Doc change
• gatsby-cli version (gatsby --version): N/A - Doc change
• Node.js version: node -v: v9.7.1
• Operating System: macOS High Sierra 10.13.4

File contents (if changed):

CONTRIBUTION.md:
* Clone your fork: git clone https://github.com//gatsby.git``

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[m-allanson]

Thanks for the change and detailed write-up!

[jlengstorf]

Hiya @TylerSanford! 👋

This is definitely late, but on behalf of the entire Gatsby community, I wanted to say thank you for being here.

Gatsby is built by awesome people like you. Let us say “thanks” in two ways:

1. We’d like to send you some Gatsby swag. As a token of our appreciation, you can go to the Gatsby Swag Store and log in with your GitHub account to get a coupon code good for one free piece of swag. (We’ve got t-shirts and hats, plus some socks that are really razzing our berries right now.)
2. If you’re not already part of it, we just invited you to join the Gatsby organization on GitHub. This will add you to our team of maintainers. You’ll receive an email shortly asking you to confirm. By joining the team, you’ll be able to label issues, review pull requests, and merge approved pull requests.

If you have questions, please don’t hesitate to reach out to us: tweet at @gatsbyjs and we’ll come a-runnin’.

Thanks again! 💪💜