Add dist and other ignores to .gitignore during create

[karlhorky]

During scaffolding with extension@latest create, it would be great to:

1. Create a .gitignore (if one does not exist)
2. Add a line for each path which should be ignored (only if the lines are not already present, similar to fix: don't duplicate .gitignore entries microsoft/create-playwright#122)

This is similar to what @jmg-duarte suggested:

• Add option to initialize git along with the project #54 (comment)

But the PR closing issue #54 did not include .gitignore support:

• Initialize git during creation #121

Some ideas for paths that could be ignored:

• dist
• extension.d.ts (as per the TypeScript docs)

[jmg-duarte]

You should be able to just write the .gitignore in this line — https://github.com/extension-js/extension.js/pull/121/files#diff-c79a9d3ab27d3a96709ef6bb93d65fe51be0b7fde2d7f60d5821d2e15f2173aeR64

Something like

fs.writeFile(".gitignore", gitignoreContents, (err) => { /* TODO: error handling */ })

As for the contents, without interaction I'd just cherry pick them from https://github.com/github/gitignore/blob/main/Node.gitignore

And add other paths that might be relevant

[cezaraugusto]

hi folks, thanks for the feedback!

there is a PR open for this request in #158, feel free to review/suggest changes!