Update changelog for 2.4.0

[zklaus]

Description

This updates the changelog for version 2.4.0 to rc1 status

---

Checklist

It is the responsibility of the author to make sure the pull request is ready to review. The icons indicate whether the item will be subject to the 🛠 Technical or 🧪 Scientific review.

• 🛠 This pull request has a descriptive title and labels
• 🛠 Code is written according to the code quality guidelines
• 🧪 and 🛠 Documentation is available
• 🛠 The list of authors is up to date
• 🛠 All checks below this pull request were successful

---

To help with the number pull requests:

• 🙏 We kindly ask you to review two other open pull requests in this repository

[codecov]

Codecov Report

Merging #1366 (4f425bf) into main (bfb2fba) will not change coverage.
The diff coverage is n/a.

❗ Current head 4f425bf differs from pull request most recent head 5bf8144. Consider uploading reports for the commit 5bf8144 to get more accurate results

@@           Coverage Diff           @@
##             main    #1366   +/-   ##
=======================================
  Coverage   88.37%   88.37%           
=======================================
  Files         195      195           
  Lines        9943     9943           
=======================================
  Hits         8787     8787           
  Misses       1156     1156           

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update bfb2fba...5bf8144. Read the comment docs.

[valeriupredoi]

Looking good, man! may want to remove the Notebook/API section if there's nothing in there, also - did we not want to have Highlights in?

[zklaus]

Good call on the empty section. I think we should add the highlights for the final release and not yet for the release candidate.

[valeriupredoi]

sounds good, man 🍺