Fix MTOM sample build failure caused by spring-boot-starter in lib/

The axis2-spring-boot-starter JAR in the distribution lib/ directory
caused WSDL2Java codegen to crash with ClassNotFoundException for
org.springframework.core.env.Environment — Spring Framework JARs are
explicitly excluded from the distribution but the starter references
them. The codegen process exits with code 1, producing no generated
sources, then the MTOM skeleton compile fails.

Remove axis2-openapi, axis2-mcp-bridge, axis2-spring-boot-starter,
and axis2-jpa-schema from the distribution pom. These modules are
published to Maven Central as standalone artifacts consumed via
Maven dependency, not via the binary distribution ZIP. Also remove
jackson and spring-boot-autoconfigure legal files that were only
needed for the now-excluded distribution dependencies.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: robertlazarski