Add tests to validate 1.x tables are readable with 0.16.0 hudi

We need tests added to 0.16.0 hudi to ensure it can read 1.x tables. 

We should have good coverage for all new log formats, diff table types, pending compactions, pending clustering, completed clustering, failed commits/delta commits, pending rollbacks, pending cleans etc. diff payloads, key gen, partitioned/non-partitioned. regular index and global index.

Cover all different writers:

a. spark ds writer

b. spark sql

c. deltastreamer 

d. spark streaming writer 

Reader side validation:

lets account for snapshot read, incremental read, time travel read.