[v2.1.1] - Expose Folder Property for Groups and Nodes

• Add a folder property to each node and group (#160)
• Bump pyupgrade from 2.7.3 to 2.10.0 (#149 & #151)
• Bump pylint from 2.6.0 to 2.7.0 (#158)
• Bump isort from 5.6.4 to 5.7.0 (#146)
• Bump codespell from 1.17.1 to 2.0.0 (#143)