Enhance RIGHT DB actions for clusters where user has limited rights but DB prepared for mirroring

[jkovacs-hwx]

In case if user has limited DB level permissions - like can work with tables but can't change DB attributes - some actions/statements needs to be configurable for successful mirroring:

• Skip the ALTER DB [MANAGED]LOCATION statement(s) if it would be the same as what already set for the existing DB or if the user sets a spec session option
• Skip the ALTER DB OWNER statement is user sets a spec session option

[jkovacs-hwx]

The DB location change could cause issues if altering location is skipped and tables would be mirrored to new location, but then this could be more complex like:

• if location is changed in a way that old/new managed/external location would switch that could cause conflicts
• mirroring a set of tables from one source into a DB where other set of tables are mirrored from other source with mixed locations could cause conflicts

In these cases I think the user needs to set up proper 'relocation' configuration rather expect hms-mirror to handle automatic mapping. The only auto-mapping could be changing managed table locations from custom locations to the strict MANAGEDLOCATION in newer hive versions