Release 0.2.0-beta

• Change version in build config (!187 (merged))
• Update translations
• Tag in Git
• Update changelog
• Build release files with GitLab CI (https://code.briarproject.org/briar/briar-desktop/-/pipelines/10047)
• Copy release files to desktop.briarproject.org
• Check that permalink points to correct version
• Inform 3rd party maintainers about release
• Update hashsums on website (website!84 (merged))
• Post on social media (Mastodon, Twitter)