Drop support for Python 3.6

[valeriupredoi]

Description

Closes #1199
Related to full functionality of #1182
Tests failing due to problem fixed in #1197

Link to documentation:

---

Before you get started

• ☝ Create an issue to discuss what you are going to do

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
• 🛠 Any changed dependencies have been added or removed correctly
• 🛠 All checks below this pull request were successful - No, but see what I says above

---

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 #1200 (24a0249) into main (2a0bb11) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #1200   +/-   ##
=======================================
  Coverage   85.54%   85.54%           
=======================================
  Files         188      188           
  Lines        9150     9150           
=======================================
  Hits         7827     7827           
  Misses       1323     1323           

---

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 2a0bb11...24a0249. Read the comment docs.

[valeriupredoi]

@bouweandela @zklaus we should talk about this at the meeting tomorrow 👍

[zklaus]

Agree with the idea, have not yet checked the implementation.

[valeriupredoi]

cool! have a look when you gots time 👍

[zklaus]

Will do once we decide to go ahead with this. 🍻

[valeriupredoi]

OK if we do it in 2.4 then let's just get #1182 and #1197 in and I'll just take 3.6 out the Github Action tests, basically we will have no support for it via those two PRs but not saying it explicitly in our docs and environment file

[bouweandela]

The conda build is taking too long, but it looks unrelated to this pull request.