Removed Connection::project()

The methods has more limitations and caveats than provides real use:

1. It fetches all data in memory which is often inefficient (see #2718).
2. It fetches rows in memory one by one instead of using `fetchAll()`.
4. It doesn't allow to specify the statement fetch mode since it's instantiated internally.
5. It can be easily replaced with:
   ```php
   foreach ($conn->executeQuery($query, $params, $types) as $value) {
      yield $function($value);
   }
   ```

UPGRADE.md

 # Upgrade to 3.0
 
+## BC BREAK `Statement::project()` has been removed
+
+- The `Statement::project()` method has been removed. Use `::executeQuery()` and fetch the data from the statement using one of the `Statement::fetch*()` methods instead.
+
 ## BC BREAK `::errorCode()` and `::errorInfo()` removed from `Connection` and `Statement` APIs
 
 The error information is available in `DriverException` thrown in case of an error.

src/Connection.php

@@ -1187,34 +1187,6 @@ class Connection implements DriverConnection
         return $stmt;
     }
 
-    /**
-     * Executes an, optionally parametrized, SQL query and returns the result,
-     * applying a given projection/transformation function on each row of the result.
-     *
-     * @deprecated
-     *
-     * @param string  $query    The SQL query to execute.
-     * @param mixed[] $params   The parameters, if any.
-     * @param Closure $function The transformation function that is applied on each row.
-     *                           The function receives a single parameter, an array, that
-     *                           represents a row of the result set.
-     *
-     * @return mixed[] The projected result of the query.
-     */
-    public function project($query, array $params, Closure $function)
-    {
-        $result = [];
-        $stmt   = $this->executeQuery($query, $params);
-
-        while ($row = $stmt->fetch()) {
-            $result[] = $function($row);
-        }
-
-        $stmt->closeCursor();
-
-        return $result;
-    }
-
     public function query(string $sql) : ResultStatement
     {
         $connection = $this->getWrappedConnection();