test: add alias replace externals tests in bundleless mode

[Timeless0911]

Summary

In bundleless mode, since there is no bundling concept, all modules will be externalized, so we will automatically replace the aliases in resolve.alias with output.externals to ensure the final output is generated correctly.

Related Links

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

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[codspeed-hq]

CodSpeed Performance Report

Merging #581 will not alter performance

_{Comparing test/alias-externals (bd09c42) with main (ac486b9)}

Summary

✅ 5 untouched benchmarks

[fi3ework]

Do we need to also add new test cases that rewritten with resolve.alias of the cases under tests/integration/externals/browser which is using output.externals now, since we're might encourage user to use resolve.alias first in the future.

[Timeless0911]

Do we need to also add new test cases that rewritten with resolve.alias of the cases under tests/integration/externals/browser which is using output.externals now, since we're might encourage user to use resolve.alias first in the future.

This case is a bundle case, so I add bundleless tests with resolve.alias in tests/integration/alias tests.