chore: remove obsolete script definitions

[MikeMcC399]

Issue

package.json contains several script definitions which refer to script sources that no longer exist.

https://github.com/cypress-io/cypress-docker-images/blob/b9525720b9e4e44ee7ded7f974dae89cc0dfd6f3/package.json#L10-L14

• The script sources were removed as part of PR https://github.com/cypress-io/cypress-docker-images/pull/812

Change

Remove the following obsolete script definitions from package.json:

• build
• add:base
• add:browser
• add:included

[cypress-app-bot]

• Create a Draft Pull Request if your PR is not ready for review. Mark the PR as Ready for Review when you're ready for a Cypress team member to review the PR.