* 'master' of github.com:spotify/backstage: (30 commits)
fix(techdocs-core): use the content of the readme as long description for the pypi package (#2578)
chore: add contrib to CONTRIBUTING.md (#2585)
Fix typo (#2584)
backend-common: default config env to development
v0.1.1-alpha.23
TechDocs: Inject CSS transformer and initial backstage style integration for reader (#2560)
bug(gql): use import to import the graphql module
Rename file
[blog] Announce CNCF Sandbox (#2568)
document cleaning - tutorial quickstarts (#2520)
Simplify codecov flag names
chore(scaffolder-backend): typo in visibility
Kubernetes plugins boilerplate (#2559)
CHANGELOG: add entry for SessionApi refactor
Upload package specific code coverage to codecov
Add codecov flags for core and core-api packages
TechDocs: Enable allowVulnerableTags in sanitize-html (#2554)
chore: trust the Boolean :)
docs: regenerate api reference docs
core: refactor SessionStateApi to SessionApi with sign-in/out
...