False-positive when validating a nested datetime in an array of hashes

Hey all, first of all thanks for the great library, we're using this gem a lot (alongside a variety of other tools from the dry-rb ecosystem) and find it super-useful :tada: . Thank you all for the work you're putting into these great tools!

## Describe the bug

I have encountered a very strange behaviour when dealing with validations on hashes inside an array, where the nested datetime fails to validate, whereas the same rule at the top level works just fine.

## To Reproduce

```ruby
require "pp"
require "dry-validation"
module Types
include Dry.Types(default: :nominal)
end

class Hmm < Dry::Validation::Contract
params do
optional(:works_at).filled(Types::Params::DateTime)

optional(:widgets).maybe(:array).each do
hash do
optional(:fails_at).filled(Types::Params::DateTime)
end
end
end
end

pp Hmm.new.call(works_at: Time.now.iso8601, widgets: [{fails_at: Time.now.iso8601}]).errors.to_h
# => {:widgets=>{0=>{:fails_at=>["must be a date time"]}}}
```

## Expected behavior

The example above should be valid, but is not. I also tried experimenting with a variety of other types but all have the same issue.

## My environment

- Affects my production application: YES (such that I cannot make valid parameters pass through my contract)
- Ruby version: 3.2.2
- OS: Linux
- dry-validation 1.10.0 (latest)
- dry-schema 1.13.3 (latest)
- dry-types 1.7.1 (latest)