Check hashes of migration files to warn about accidental edits

[sweatybridge]

Is your feature request related to a problem? Please describe.
No warning is shown when user changed an already applied migration file.

Describe the solution you'd like
When running db push, we should check the hash of migration files to warn about cases where they deviate from remote history table.

Describe alternatives you've considered
Nil

Additional context
Add any other context or screenshots about the feature request here.