Instructions to release a new Spyder version

To release a new version of Spyder you need to follow these steps:

Update translation strings (at least one week before the release)

Install gettext-helpers from source.
Create a new PR to update our *.pot and *.po files by running
```
spyder-gettext scan spyder
```
Check that no warnings are emitted by that command. If they are, then fix them in the same PR.
Merge that PR.
Close the current translation PR, i.e. the one with the title New Crowdin updates.
Delete the translate/<branch-name> branch associated to that PR.
Go to the integrations page on Crowdin:

https://crowdin.com/project/spyder/settings#integration-github
Press Sync now there to open a new translation PR.
Send a message to translators on Crowdin to update their translations:

https://crowdin.com/messages

An example of that message can be found in

spyder-ide#14117

Checkout the translations branch with
```
git checkout translate/<branch-name>
```
Squash all commits in that branch to leave only one with the message

Update and compile translations
Generate the mo files by running
```
spyder-gettext compile spyder
```
Remove mo files that are still not part of version control.
Add those files to the previous commit with
```
git add .
git commit --amend --no-edit
```
Rename the PR title to be PR: Update translations from Crowdin.
Merge the PR.
Don't forget to remove your local checkout of translate/<branch-name> because that's going to be outdated for next time.

Release a new version of spyder-kernels, if required.
Release a new version of python-language-server, if required.
Create a new branch in Spyder with the name update-core-deps
Update the versions of those packages in the following files
- setup.py
- spyder/dependencies.py
- spyder/plugins/ipythonconsole/plugin.py

Commit with

git add .
git commit -m "Update core dependencies"

Update their respective subrepos with the following commands, but only if new versions are available!

git subrepo pull external-deps/spyder-kernels
git subrepo pull external-deps/python-language-server

Close the current milestone Github
git pull or git fetch/merge
Update CHANGELOG.md with loghub spyder-ide/spyder -m vX.X.X
Add sections for New features and Important fixes in CHANGELOG.md. For this take a look at closed issues and PRs for the current milestone.
git commit -m "Update Changelog"
Update Announcements.md (this goes to our Google group)
git commit -m "Update Announcements"
git clean -xfdi and select option 1.
Update version in __init__.py (set release version, remove 'dev0')
git add . and git commit -m "Release X.X.X"
python setup.py sdist
Activate environment with pip packages only
pip install -U pip setuptools twine wheel
python3 setup.py bdist_wheel
twine check dist/*
twine upload dist/*
git tag -a vX.X.X -m 'Release X.X.X'
Update version in __init__.py (add 'dev0' and increment minor)
git add . and git commit -m "Back to work [ci skip]"
git checkout master
git merge 4.x
git commit -m "Release X.X.X [ci skip]"
git push upstream master
git push upstream 4.x
git push upstream --tags