Automate bumping of esbuild for JS/TS plugins

[pkwarren]

Currently, esbuild is a dev dependency in most JS/TS plugins to further shrink the size of each plugin by building dependencies. However, esbuild is currently a 0.x dependency so it won't automatically get a new minor version when we generate package-lock.json when creating a new plugin version.

We should automate running npm install esbuild@latest --save-dev in the fetcher code to pick up new esbuild versions automatically. See https://github.com/bufbuild/plugins/pull/1252#discussion_r1613601608 for more info.