chore(cwc): remove changelog file from gitignore (carbon-design-syste…

…m#9678)

### Related Ticket(s)

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### Description

changelog file is needed in the release process, removing from the gitignore file

### Changelog

**New**

- {{new thing}}

**Changed**

- {{changed thing}}

**Removed**

- {{removed thing}}

<!-- React and Web Component deploy previews are enabled by default. -->
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<!-- *** "test: e2e": Codesandbox examples and e2e integration tests -->
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carbon-web-components/packages/carbon-web-components/.gitignore

@@ -13,4 +13,3 @@ tests/coverage
 .env
 .npmrc
 yarn-error.log
-CHANGELOG.md