Update ctor requirement from 0.3 to 0.4

---
updated-dependencies:
- dependency-name: ctor
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

cast_checks/Cargo.toml

@@ -13,7 +13,7 @@ cast_checks_macro = { version = "=0.1.5", path = "../macro" }
 
 [dev-dependencies]
 assert_cmd = "2.0"
-ctor = "0.3"
+ctor = "0.4"
 predicates = "3.0"
 regex = "1.9"
 tempfile = "3.8"