Dependency issues

[ekashida]

With the changes in #151, some peer dependencies have become actual dependencies:

• @lwc/eslint-plugin-lwc
• @salesforce/eslint-plugin-lightning
• eslint-plugin-import
• eslint-plugin-jest

These, and any others that may have been missed, should be moved to dependencies.

[ekashida]

Not 100% sure this is an issue, it just seems strange to have to install all of these packages even when you're not using the specific config with the dependency. yarn why doesn't seem to report peer dep relationships either so you couldn't use that to remember why one of these was installed once you installed it, but I guess that issue always existed with plugins and peer deps.

[wjhsf]

It's standard practice for eslint configs to specify their plugins as peer deps. 🤷