2.4.0

• #607 Reduce footpring of EnvConfigSource
• #605 Bump docker-maven-plugin from 0.36.0 to 0.36.1
• #604 Support SmallRyeConfig injection
• #603 Improved SmallRyeConfig APIs
• #600 Add normalized env property names only when required.
• #599 Flatten HoconConfigSource.
• #598 Build with JDK 16.
• #597 Fix false validation error on unused property.
• #596 Fix documentation issue with multiple profiles.
• #594 Apply fallback if value is found but empty.
• #592 Fix skewer for property names with words.
• #590 Fix Stackoverflow in mapping with optional Group with super types.
• #589 Bump smallrye-parent from 27 to 28
• #586 Bump smallrye-parent from 26 to 27
• #584 Improve way to manage default values in case of a Map
• #582 Bump docker-maven-plugin from 0.35.0 to 0.36.0
• #579 Allow to fetch multiple config parameters as a Map
• #577 smallrye-config-source-file-system allow multiple locations (#571)
• #571 smallrye-config-source-file-system allow multiple locations
• #570 Fixed issue with property names and member names in ConfigMappings.