Address feedback from Kyle

Signed-off-by: Stephen Wakely <fungus.humungus@gmail.com>

Author: StephenWakely

docs/REVIEWING.md

@@ -37,32 +37,34 @@ following items should also be checked:
 - [ ] Does it comply with the [instrumentation spec](specs/instrumentation.md)?
 
 
-### Sink review checklist
+### Checklist - new sink
 
 This checklist is specific for Vector's sink code.
 
-## Logic
+#### Logic
 
 - [ ] Does it work? Do you understand what it is supposed to be doing?
 - [ ] Does the retry logic make sense?
 - [ ] Are the tests testing that the sink is emitting the correct metrics?
 - [ ] Are there integration tests?
 
-## Code structure
+#### Code structure
 
-- [ ] Is it using the sink prelude?
+- [ ] Is it using the sink prelude (`use crate::sinks::prelude::*`)?
+- [ ] Is the sink a stream based sink?
+      Check that the return value from `SinkConfig::build` is the return from `VectorSink::from_event_streamsink`.
 - [ ] Is it gated by sensible feature flags?
 - [ ] Is the code modularized into `mod.rs`, `config.rs`, `sink.rs`,  `request_builder.rs`, `service.rs`
 - [ ] Does the code follow our [style guidelines].
 
-## Documentation
+#### Documentation
 
-- [ ] Look at the doc preview on Netlify. Does it look good? 
+- [ ] Look at the doc preview on Netlify. Does it look good?
 - [ ] Is there a `cue` file linking to `base`?
 - [ ] Is there a markdown file under `/website/content/en/docs/reference/configuration/sinks/`?
 - [ ] Are module comments included in `mod.rs` linking to any relevant areas in the external services documentation?
 
-## Configuration
+#### Configuration
 
 - [ ] Are TLS settings configurable?
 - [ ] Are the Request settings configurable?