Avoids the breaking change in #1927: If there's a function "my_func" having a single unnamed json param and other overloaded pairs(with any number of params), PostgREST won't be able to resolve a POST request to "my_func".
Getting the value for a header GUC on PostgreSQL v14 is done using `current_setting('request.headers')::json->>'name-of-header'` and in a similar way for `request.cookies` and `request.jwt.claims`
PostgreSQL versions below 14 can opt in to the new JSON GUCs by setting the `db-use-legacy-gucs` config option to false (true by default)
Update the hasql-transaction library to version 1.0.1
Add hints and kill thread at configuration read when using incompatible pooling modes: statement pooling and transaction pooling with prepared statements enabled.
* Add 300 response for overloaded functions with same argument names but different types
* Add Path type to handle validations and errors before defining the Target
Allows using header "Prefer=headers-only" explicitly to get a response with only a Location header.
BREAKING CHANGE: Change default for POST request from headers-only to minimal
Resolves#1656
