Add a check that applied migrations have not been edited

[iDneprov]

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A large customer had a problem: colleagues applied a migration, then edited it and expected it to apply again but it didn't. As a result, there was an incident of prod failure. To prevent this from happening, we need to add a check that migrations have not been edited. A simple solution is to add the hash sum of the file to the space with the migrations applied. And check the hash sum when trying to reapply the migration.