docs: README mismatch between 'pg' library deps and 'postgres.js' (#1738)

Author: avallete

packages/sql/pg/README.md

@@ -1,6 +1,6 @@
 # `@effect/sql-pg`
 
-An `@effect/sql` implementation using the `postgres.js` library.
+An `@effect/sql` implementation using the `pg` library.
 
 ## Documentation