build: Move build related unit test into own job

[AbhiPrasad]

We shouldn't be asserting on built assets (dist/esm) in our unit tests.

This helps unblock #4616

[github-actions]

size-limit report

Path	Base Size (0b2221d)	Current Size	Change
@sentry/browser - ES5 CDN Bundle (gzipped + minified)	19.79 KB	19.79 KB	-0.01% 🔽
@sentry/browser - ES5 CDN Bundle (minified)	63.39 KB	63.39 KB	0%
@sentry/browser - ES6 CDN Bundle (gzipped + minified)	18.44 KB	18.44 KB	0%
@sentry/browser - ES6 CDN Bundle (minified)	56.42 KB	56.42 KB	0%
@sentry/browser - Webpack (gzipped + minified)	22.25 KB	22.25 KB	0%
@sentry/browser - Webpack (minified)	76.34 KB	76.34 KB	0%
@sentry/react - Webpack (gzipped + minified)	22.28 KB	22.28 KB	0%
@sentry/nextjs Client - Webpack (gzipped + minified)	46.43 KB	46.43 KB	0%
@sentry/browser + @sentry/tracing - ES5 CDN Bundle (gzipped + minified)	26.68 KB	26.68 KB	0%

[lobsterkatie]

Wow. TIL that these tests even exist (both on the browser side and the utils side).

Two things:

1. The utils test is really a types test, to make sure we're not including node types where we shouldn't be. Could we call it test/types/build.js, or even test/types/index.js since there's unlikely to ever be more than one file in that folder? (I think package is kind of ambiguous.)

2. Out of the scope of this PR, but I wonder if the browser tests are even still necessary, now that we run all of our browser integration tests against all of our bundles.

[AbhiPrasad]

Solid diligence on the review - I hastly put this together to unblock, but I maybe should have made that more clear.

I'll make the changes for test/types/index.js - it does express clarity better here.

Out of the scope of this PR, but I wonder if the browser tests are even still necessary, now that we run all of our browser integration tests against all of our bundles.

We can easily migrate this part

sentry-javascript/packages/browser/test/package/npm-build.js

Lines 60 to 68 in 50a5d9e

	const scriptEl = window.document.createElement('script');
	scriptEl.textContent = myLibrary;
	window.document.body.appendChild(scriptEl);
	// Testing https://github.com/getsentry/sentry-javascript/issues/2043
	const scriptEl2 = window.document.createElement('script');
	scriptEl2.textContent = myLibrary;
	window.document.body.appendChild(scriptEl2);
	// ------------------------------------------------------------------

, but

sentry-javascript/packages/browser/test/package/npm-build.js

Lines 55 to 58 in 50a5d9e

	if (myLibrary.indexOf('tslib_1__default') !== -1) {
	console.log('"tslib_1__default" reappeared...');
	process.exit(1);
	}

will probably need to live in a similar set up.

[lobsterkatie]

Oh, yeah. I'll admit that as far as the browser tests are concerned, I skimmed it, thought, "Oh, okay, it's just testing that the built bundle does the normal sentry stuff," and moved on. Now you’re the one doing the due diligence!

At some point we might look back at any parts of that which aren't just testing that the built bundle does a thing (superseded by Onur's recent work, IMHO) to see if all of them are even still relevant, but not urgent.