fix: add missing exports entry to dedupe-mixin package.json

[mservaising]

What I did

Fixes #2495

1. I added the export in the package.json of dedup-mixin package.

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🦋 Changeset detected

Latest commit: 523b96b

The changes in this PR will be included in the next version bump.

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Name	Type
@open-wc/dedupe-mixin	Patch

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[thepassle]

this is a breaking change

[mservaising]

ok, just to understand, why it is a breaking change ?

[thepassle]

Adding a package exports map is usually (if not always) a breaking change. In this case it will only allow imports like import { foo } from '@open-wc/dedupe-mixin'. So if anybody imports it differently, for example import { foo } from '@open-wc/dedupe-mixin/index.js', that will now no longer work

[mservaising]

then have you any other fix for the issue I got above (using ing-web 3) but I suppose it is the same with lion