Transport should depend on hive-exec core jar for the test framework

[shardulm94]

org.apache.hive:hive-exec bundles in some transitive dependencies (e.g. guava) without shading them. This causes classpath issues in the test framework as user is not able to depend on newer guava version. Instead we should use org.apache.hive:hive-exec:core jar which does not bundle transitive dependencies. This way, guava dependencies can be manipulated through Gradle dependency resolution if required.