minor #10257 Remove the changelog file (fabpot)

This PR was merged into the 2.8 branch.

Discussion
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Remove the changelog file

It does not look like it's maintained anymore, let's remove it. I know that it's gone in more recent branches, but I don't see a need to keep it in 2.8 as it's not up-to-date anyway.

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Commits
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d22af6b removed the changelog file

Author: javiereguiluz