[CI] Prepare lock file on build

See merge request !843

Removeresponsive tables for now

See merge request !838

Update dependency django-colorfield to ^0.6.0

See merge request !841

Fix ordering of changelog after merge accident

See merge request !840

Resolve "Date picker for date of birth unusable"

Closes #569

See merge request !835

Resolve "Favicon should contain only school bag"

Closes #254

See merge request !772

# Conflicts:
#   CHANGELOG.rst

Resolve "Icons/logo should be uploaded to public/"

Closes #581

See merge request !837

# Conflicts:
#   CHANGELOG.rst

Resolve ""Imprint" is called "imprint""

Closes #579

See merge request !834

# Conflicts:
#   CHANGELOG.rst

Resolve "Colours not updated / stylesheet not regenerated on preferences save"

Closes #575

See merge request !836

Resolve "Make database ssl mode configurable"

Closes #578

See merge request !833

Fix typos

See merge request !832

Update dependency django-auth-ldap to v4

See merge request !827

Release 2.3.1

See merge request !830

Resolve "Error uploading favicon to S3"

Closes #576

See merge request !829