chore(docs): background check documentation update

[pantheredeye]

Updated the documentation around automated background checks to reflect that it is

• Default enabled
• Provided example tags that can be used: latest, canary, next, or rc
• Provided options for user to disable the automated check

This information spans two documents. Since the two documents interact, I added a link from the background check section to the TOML configuration section.

[pantheredeye]

This is me guessing here on ways to disable this. I have not tested these! 🙏

[pantheredeye]

Also - I am waiting for approval/any modifications and then I will update and port back to v6(?).

[pantheredeye]

Suggested change

	Right now it defaults to check for a new `latest` version.
	Right now it defaults to check for a new "latest" version.

[Tobbe]

I think "checking" is the more correct form of the verb here 🙂

[pantheredeye]

Suggested change

	To customize this behavior - perhaps by checking for `rc` (release candidate) or other tags - set `notifications.versionUpdates` in the `redwood.toml` file to include an array of the tags you're interested in.
	To customize this behavior - perhaps by checking for "rc" (release candidate) or other tags - set `notifications.versionUpdates` in the `redwood.toml` file to include an array of the tags you're interested in.

[pantheredeye]

Suggested change

	While you can specify any tag, common options include: `latest`, `canary`, `next`, or `rc`.
	While you can specify any tag, common options include: "latest", "canary", "next", or "rc" "experimental", or a valid semver version.

These notes exist in the upgrade.js file... if these are all still valid tags, then I will update this PR to the above suggestion.

    .option('tag', {
      alias: 't',
      description:
        '[choices: "latest", "rc", "next", "canary", "experimental", or a specific-version (see example below)] WARNING: "canary", "rc" and "experimental" are unstable releases! And "canary" releases include breaking changes often requiring codemods if upgrading a project.',
      requiresArg: true,
      type: 'string',
      coerce: validateTag,
    })

and

  if (!isTagValid) {
    // Stop execution
    throw new Error(
      c.error(
        "Invalid tag supplied. Supported values: 'rc', 'canary', 'latest', 'next', 'experimental', or a valid semver version\n",
      ),
    )
  }

[Tobbe]

If you're going with your suggestion Barrett there are a couple of small tweaks I'd do to it. Right now there are two "or", and a missing comma.

With those corrections it'd look like this:

While you can specify any tag, common options include: "latest", "canary", "next", "rc", "experimental", or a valid semver version.

I'll let @Josh-Walker-GM comment on the validity of all those choices