Function compareMigrationHashes

Compares hashes from migration files with migration records from the database. Execution order:

1. Load all migration files from the committed folder.
2. Extract migration number, hash, and previous hash from each migration file.
3. Load all migration records from graphile_migrate.migrations table.
4. Compare file records with records from the database:
   • Checks if migration history has more records than committed migration files.
   • Checks for mismatches in hashes. A mismatch is considered a file record where the migration file number exists in the database, but the hash(or previous hash) recorded in the database doesn't match hash(or previous hash) in file migration.