plotly.js bundle isn't rebuilt when generating schema #7538

Description

The plotly.js schema is generated using the command npm run schema. This uses the bundle at build/plotly.js. However, this bundle is only built when the dev server is running. If library files have been edited without the dev server running, those changes won't be picked up when generating the schema.

Steps to reproduce

• Be on master without the dev server running
• Edit an attribute file
• Run npm run schema
• Review the resulting plot-schema.json file and note that it doesn't include the new changes

Notes

• We could add an npm script that builds the bundle separately and then call that in npm run schema before the schema is built
• There's probably a larger refactor that could simplify the ESBuild process, but this would at least protect us when updating the schema for future PRs