Include ReflectFromReflect in all dynamic data types. (#17453)

# Objective

Fixes #17416

## Solution

I just included ReflectFromReflect in all macros and implementations. I
think this should be ok, at least it compiles properly and does fix the
errors in my test code.

## Testing

I generated a DynamicMap and tried to convert it into a concrete
`HashMap` as a `Box<dyn Reflect>`. Without my fix, it doesn't work,
because this line panics:

```rust
let rfr = ty.data::<ReflectFromReflect>().unwrap();
```

where `ty` is the `TypeRegistration` for the (matching) `HashMap`.

I don't know why `ReflectFromReflect` wasn't included everywhere, I
assume that it was an oversight and not an architecture decision I'm not
aware of.

# Migration Guide

The hasher in reflected `HashMap`s and `HashSet`s now have to implement
`Default`. This is the case for the ones provided by Bevy already, and
is generally a sensible thing to do.

crates/bevy_reflect/src/impls/std.rs

@@ -566,6 +566,7 @@ macro_rules! impl_reflect_for_veclike {
             fn get_type_registration() -> TypeRegistration {
                 let mut registration = TypeRegistration::of::<$ty>();
                 registration.insert::<ReflectFromPtr>(FromType::<$ty>::from_type());
+                registration.insert::<ReflectFromReflect>(FromType::<$ty>::from_type());
                 registration
             }
 
@@ -810,11 +811,12 @@ macro_rules! impl_reflect_for_hashmap {
         where
             K: FromReflect + MaybeTyped + TypePath + GetTypeRegistration + Eq + Hash,
             V: FromReflect + MaybeTyped + TypePath + GetTypeRegistration,
-            S: TypePath + BuildHasher + Send + Sync,
+            S: TypePath + BuildHasher + Send + Sync + Default,
         {
             fn get_type_registration() -> TypeRegistration {
                 let mut registration = TypeRegistration::of::<Self>();
                 registration.insert::<ReflectFromPtr>(FromType::<Self>::from_type());
+                registration.insert::<ReflectFromReflect>(FromType::<Self>::from_type());
                 registration
             }
 
@@ -1035,11 +1037,12 @@ macro_rules! impl_reflect_for_hashset {
         impl<V, S> GetTypeRegistration for $ty
         where
             V: FromReflect + TypePath + GetTypeRegistration + Eq + Hash,
-            S: TypePath + BuildHasher + Send + Sync,
+            S: TypePath + BuildHasher + Send + Sync + Default,
         {
             fn get_type_registration() -> TypeRegistration {
                 let mut registration = TypeRegistration::of::<Self>();
                 registration.insert::<ReflectFromPtr>(FromType::<Self>::from_type());
+                registration.insert::<ReflectFromReflect>(FromType::<Self>::from_type());
                 registration
             }
 
@@ -1301,6 +1304,7 @@ where
     fn get_type_registration() -> TypeRegistration {
         let mut registration = TypeRegistration::of::<Self>();
         registration.insert::<ReflectFromPtr>(FromType::<Self>::from_type());
+        registration.insert::<ReflectFromReflect>(FromType::<Self>::from_type());
         registration
     }
 }
@@ -1665,6 +1669,7 @@ impl GetTypeRegistration for Cow<'static, str> {
         let mut registration = TypeRegistration::of::<Cow<'static, str>>();
         registration.insert::<ReflectDeserialize>(FromType::<Cow<'static, str>>::from_type());
         registration.insert::<ReflectFromPtr>(FromType::<Cow<'static, str>>::from_type());
+        registration.insert::<ReflectFromReflect>(FromType::<Cow<'static, str>>::from_type());
         registration.insert::<ReflectSerialize>(FromType::<Cow<'static, str>>::from_type());
         registration
     }
@@ -2126,6 +2131,7 @@ impl GetTypeRegistration for &'static Path {
     fn get_type_registration() -> TypeRegistration {
         let mut registration = TypeRegistration::of::<Self>();
         registration.insert::<ReflectFromPtr>(FromType::<Self>::from_type());
+        registration.insert::<ReflectFromReflect>(FromType::<Self>::from_type());
         registration
     }
 }
@@ -2419,6 +2425,7 @@ impl GetTypeRegistration for &'static Location<'static> {
     fn get_type_registration() -> TypeRegistration {
         let mut registration = TypeRegistration::of::<Self>();
         registration.insert::<ReflectFromPtr>(FromType::<Self>::from_type());
+        registration.insert::<ReflectFromReflect>(FromType::<Self>::from_type());
         registration
     }
 }