Resynch utils and common from common-src and use new FlowDirection fix

Changes

• Resynch with common-src
• Removed unused code
• Removed code that is part of common-src now - especially utils and common
• Also moved to new CPR-based HTTP client in common-src

Fixes reading of FlowDirection from YAML

Common-src MR: oai-cn5g-common-src!58 (merged)