error[E0277]: this type is outside the Sausage schema subset
 --> tests/ui/subset.rs:6:12
  |
6 |     value: std::collections::HashMap<String,String>,
  |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `SchemaType` is not implemented for `HashMap<std::string::String, std::string::String>`
  |
  = help: the following other types implement trait `SchemaType`:
            ()
            Bad
            Vec<T>
            bool
            f32
            f64
            i16
            i32
          and $N others
note: required by a bound in `supported`
 --> tests/ui/subset.rs:3:1
  |
3 | #[sausage_plugin::schema]
  | ^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `supported`
  = note: this error originates in the attribute macro `sausage_plugin::schema` (in Nightly builds, run with -Z macro-backtrace for more info)