Release v0.3.0

What's Changed

• Add docker image for the workflows-manager by @dl1998 in #33
• Fix architecture diagram image in the documentation by @dl1998 in #34
• Add sudo to install command by @dl1998 in #35
• Update version to 0.3.0 by @dl1998 in #36
• Remove arm/v7 platform by @dl1998 in #37

Full Changelog: v0.2.0...v0.3.0