db.pg: fix typos (#19654)

Author: asvln

vlib/db/pg/README.md

@@ -45,7 +45,7 @@ gem install pg -- --with-pg-config=/opt/local/lib/postgresql[version number]/bin
 
 **ArchLinux**: `pacman -S postgresql-libs`
 
-##Getting Started with [PostgreSQL](https://www.postgresqltutorial.com/postgresql-getting-started)
+## Getting Started with [PostgreSQL](https://www.postgresqltutorial.com/postgresql-getting-started)
 
 Read this section to learn how to install and connect to PostgreSQL
 [*Windows*](https://www.postgresqltutorial.com/install-postgresql);

vlib/db/pg/pg.v

@@ -279,7 +279,7 @@ pub fn (db DB) exec_param_many(query string, params []string) ![]Row {
 	}
 }
 
-// exec_param2 executes a query with 1 parameter ($1), and returns either an error on failure, or the full result set on success
+// exec_param executes a query with 1 parameter ($1), and returns either an error on failure, or the full result set on success
 pub fn (db DB) exec_param(query string, param string) ![]Row {
 	return db.exec_param_many(query, [param])
 }