fix: use js loader for .cjs and .mjs files

[angeloashmore]

This PR adds support for .cjs and .mjs files by overriding their loader to js.

Per esbuild's js loader docs, the js loader supports .cjs and .mjs files and treats them the same as .js files.

Without this PR, importing a .cjs or .mjs file prints the following error:

Error: Invalid loader: "cjs" (valid: js, jsx, ts, tsx, css, json, text, base64, dataurl, file, binary)

› /[project-path]/node_modules/esbuild/lib/main.js:1209:25
› /[project-path]/node_modules/esbuild/lib/main.js:606:9
› handleIncomingPacket (/[project-path]/node_modules/esbuild/lib/main.js:701:9)
› readFromStdout (/[project-path]/node_modules/esbuild/lib/main.js:573:7)
› runServiceSync (/[project-path]/node_modules/esbuild/lib/main.js:1808:3)
› buildSync (/[project-path]/node_modules/esbuild/lib/main.js:1628:3)
› compile (/[project-path]/register.js:112:39)
› requireExtensions.<computed> (/[project-path]/register.js:164:28)