Readme: fix link to chrome web store

[wmertens]

Issue / feature description

The current link points to the outdated store, which was discontinued in January.

Changes

Fix link

Checklist

• [x] Rebased to the last commit of the target branch (or merged)
• [x] Code self-reviewed
• [x] Code self-tested
• [x] Tests updated (if needed)
• [x] All tests are passing locally

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