code monitors: enable webhooks for everyone

Created by: limitedmage

Closes #32221 (closed) Closes #10212 (closed)

• Add Beta label to feature in product
• Enable feature flag
• Update changelog
• Update docs with feature as Beta

Test plan

• All existing CI should pass.
• Chromatic should show Slack and Webhook sections in code monitoring form storybook tests.

App preview:

• Web
• Storybook

Check out the client app preview documentation to learn more.