ESLint rules have been added to enforce our JSDoc conventions. These
rules were introduced by updating `@metamask/eslint-config` to v9.
Some of the rules have been disabled because the effort to fix all lint
errors was too high. It might be easiest to enable these rules one
directory at a time, or one rule at a time.
Most of the changes in this PR were a result of running
`yarn lint:fix`. There were a handful of manual changes that seemed
obvious and simple to make. Anything beyond that and the rule was left
disabled.
The ESLint config for the extension explicitly includes support for
Prettier. However, this is already being provided by our global ESLint
config (`@metamask/eslint-config`). Therefore there is no need to
include it here. In fact, this is causing weird issues where the `curly`
option is getting overridden somehow. After this change, these syntaxes
are invalid:
``` javascript
if (foo) return;
```
``` javascript
if (foo) return 'bar';
```
A redundant comparison for the `EIP_1559_V2_ENABLED` variable has been
removed. This variable is a boolean, so it can be treated as a boolean
directly in most cases.
One such comparison has been preserved for the purpose of allowing unit
testing, because `process.env` entries are always strings in Node.js. A
comment was added to explain this.
