feat: add one to one relationship for embedding

BREAKING CHANGE: For the cases where one to one relationships are
detected, json objects will be returned instead of json arrays of length
1.

If you wish to override this behavior, you can use computed
relationships to return arrays again.

CHANGELOG.md

@@ -40,6 +40,8 @@ This project adheres to [Semantic Versioning](http://semver.org/).
    + Different options for the plan can be used with the `options` parameter: `Accept: application/vnd.pgrst.plan; options=analyze|verbose|settings|buffers|wal`
    + The plan can be obtained in text or json by using different media type suffixes: `Accept: application/vnd.pgrst.plan+text` and `Accept: application/vnd.pgrst.plan+json`.
  - #2144, Allow extending/overriding relationships for resource embedding - @steve-chavez
+ - #1984, Detect one-to-one relationships for resource embedding  - @steve-chavez
+   + Detected when there's a foreign key with a unique constraint or when a foreign key is also a primary key
 
 ### Fixed
 
@@ -81,6 +83,8 @@ This project adheres to [Semantic Versioning](http://semver.org/).
    + This embedding form was easily made ambiguous whenever a new view was added.
    + For migrating, clients must be updated to the embedding form of `/view?select=*,other_view!column(*)`.
  - #2312, Using `Prefer: return=representation` no longer returns a `Location` header - @laurenceisla
+ - #1984, For the cases where one to one relationships are detected, json objects will be returned instead of json arrays of length 1
+   + If you wish to override this behavior, you can use computed relationships to return arrays again
 
 ## [9.0.1] - 2022-06-03