Resolve "About page fails to load if app with unkown licence is installed"

Closes #872

See merge request !1271

Correctly save task status

See merge request !1267

Update dependency django-colorfield to ^0.9.0

See merge request !1263

Prepare release 3.1

See merge request !1264

Translations update from Weblate

See merge request !1219

Translations update from Weblate

See merge request !1240

Currently translated at 84.7% (133 of 157 strings)

Translation: AlekSIS/AlekSIS-Core-Frontend
Translate-URL: https://translate.edugit.org/projects/aleksis/aleksis-core-frontend/ru/

Currently translated at 100.0% (157 of 157 strings)

Translation: AlekSIS/AlekSIS-Core-Frontend
Translate-URL: https://translate.edugit.org/projects/aleksis/aleksis-core-frontend/uk/

Resolve "Urls in confimation email contains the /django/ prefix"

Closes #852

See merge request !1253

Resolve "Improve performance of polling queries"

Closes #847

See merge request !1252

Resolve "Fix whoAmI query" (and make permission query poll)

Closes #860

See merge request !1250

Resolve "Doc for maintainance tasks still mentions yarn install"

Closes #861

See merge request !1251

Merge branch '856-language-select-uses-english-as-default-language-and-not-browser-language' into 'master'

Resolve "Language select uses English as default language (and not browser language)"

Closes #856

See merge request !1245

Merge branch 'master' into '856-language-select-uses-english-as-default-language-and-not-browser-language'

# Conflicts:
#   CHANGELOG.rst

Resolve "Fix metrics URL (/django/)"

Closes #858

See merge request !1246

# Conflicts:
#   CHANGELOG.rst

Resolve "Update material design icons"

Closes #851

See merge request !1242

Resolve "Include dynamic titles in app bar of new SPA"

Closes #859

See merge request !1243

# Conflicts:
#   CHANGELOG.rst
#   aleksis/core/frontend/index.js

Resolve "Include correct Vuetify translations"

Closes #857

See merge request !1244

# Conflicts:
#   CHANGELOG.rst

Resolve "Language select is sometimes not shown due to overlengh in sidenav"

Closes #853

See merge request !1247