Disable doctests for derive code snippets

docs/_includes/attributes.md

@@ -296,7 +296,7 @@ Set the path to the schemars crate instance the generated code should depend on.
 
 Sets properties specified by [validator attributes](#supported-validator-attributes) on items of an array schema. For example:
 
-```rs
+```rust,compile_fail
 struct Struct {
     #[schemars(inner(url, regex(pattern = "^https://")))]
     urls: Vec<String>,
@@ -329,7 +329,7 @@ Set on a container, variant or field to run a `schemars::transform::Transform` a
 
 The `Transform` trait is implemented on functions with the signature `fn(&mut Schema) -> ()`, allowing you to do this:
 
-```rust
+```rust,compile_fail
 fn my_transform(schema: &mut Schema) {
    todo!()
 }

docs/_includes/deriving.md

@@ -4,7 +4,7 @@ The most important trait in Schemars is `JsonSchema`, and the most important fun
 
 Usually, all you need to do to use it is to add a `#[derive(JsonSchema)]` attribute to your type:
 
-```rust
+```rust,compile_fail
 use schemars::{JsonSchema, schema_for};
 
 #[derive(JsonSchema, Debug)]