Current status of LTS group/ backporters

[marco-ippolito]

Quoting documentation https://github.com/nodejs/Release/blob/main/GOVERNANCE.md:

LTS:

For releasing on LTS release lines, releasers must:

Be added as members of the GitHub [LTS team](https://github.com/orgs/nodejs/teams/lts)
Fully release at least one Current Node.js release; for practice, and to help promote the new GPG key to the user ecosystem prior to it being required to verify an LTS release

Backporters https://github.com/nodejs/Release?tab=readme-ov-file#lts-staging-branches:

Only members of @nodejs/backporters should land commits onto staging branches.

Currently we are not enforcing both of these rules. I think we should remove the LTS team and keep only releasers, and keep the backporters for people who want to start getting involved with the release working group and can prepare current releases.