Improving the Contributor Docs

[ayeshag7]

Hello, everyone! While I was working on my pull request, I ran into errors when I tried to run the linting check as well as the test suite.
For example, when I ran npm run lint, I got the following error:

> [email protected] lint
> eslint client server --ext .jsx --ext .js

node:internal/modules/cjs/loader:998
  throw err;
  ^

Error: Cannot find module 'C:\Users\FUTURE LAPTOP\p5.js-web-editor\node_modules\eslint\bin\eslint.js'

Node.js v18.12.1

I saw a somewhat similar error when I tried to run npm run test. Trying to install the required dependencies using npm install gave me a bunch of other errors.

It took me some time to figure out that:
(a) I've to have the correct version of node, i.e., v16.14.2
(b) I can't directly run npm install at the moment. I have to run npm install --legacy-peer-deps instead because of conflicting versions of some packages being used. (This was mentioned in an issue which I found after some digging).

These pieces of information weren't mentioned in the contributor docs (or I may have missed them somehow, but I read them repeatedly while trying to fix these issues). In my opinion, we should add these as well as other potential edge cases to the contributor docs, as facing such issues may be discouraging to new developers and may prevent them from contributing to the project.

If the community agrees that it is something worth discussing and solving, I would like to make these and other possible improvements in the contributor docs.