Support building logical pipelined regions from JobGraph

Logical pipelined region partitioning is needed by FLINK-14060 to determine JobVertex slot sharing group.
We can leverage PipelinedRegionComputeUtil#computePipelinedRegions to do this by adapting JobGraph to a base Topology.

With changes from FLINK-14453, we can build LogicalPipelinedRegions from JobGraph by:
1. Introduce LogicalTopology which extends Topology
2. Implement DefaultLogicalTopology as an adapter of JobGraph to LogicalTopology
3. Add DefaultLogicalTopology#getLogicalPipelinedRegions to return the logical pipelined regions of a JobGraph