feat: remove Node.js 18 from supported versions

[alfrol]

Node.js 18 is EOL and will not receive bug fixes or security upgrades. Users should migrate to Node.js 20 or 22.

BREAKING CHANGE: Projects using create-twilio-function, plugin-asset, plugin-serverless or twilio-run will have to migrate to Node.js 20 or 22.

Contributing to Twilio

All third-party contributors acknowledge that any contributions they provide will be made under the same open-source license that the open-source project is provided under.

• I acknowledge that all my contributions will be made under the project's license.

[changeset-bot]

🦋 Changeset detected

Latest commit: cd6af04

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 5 packages

Name	Type
@twilio-labs/serverless-twilio-runtime	Major
create-twilio-function	Major
@twilio-labs/plugin-serverless	Major
@twilio-labs/plugin-assets	Major
twilio-run	Major

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[welcome]

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