Release v0.4.0

Release 0.4.0:

• Dropping support for Python 3.6. Moving to Python 3.7 to 3.9
• Adding upper pins to requirements file (edgetest)

General housekeeping

• CLA and setup cleanup by @fdosani in #115
• Removing old requirements by @fdosani in #116
• Update CODEOWNERS by @fdosani in #117
• adding ROADMAP details by @fdosani in #118
• Create publish-docs.yml by @fdosani in #123

Adding edgetest

• edgetest bump by @fdosani in #122

Full Changelog: v0.3.8...v0.4.0