migrator: Do some cleanup (#24687)

This PR does some clean up of the `migrator` crate:

- Remove `.unwrap`s
- Don't suppress `rustfmt`

Release Notes:

- N/A

crates/migrator/Cargo.toml

@@ -13,6 +13,7 @@ path = "src/migrator.rs"
 doctest = false
 
 [dependencies]
+anyhow.workspace = true
 collections.workspace = true
 convert_case.workspace = true
 log.workspace = true