Bug: Model()->find(null) should return null value

[SunilEver]

Describe the bug
When passing null in the find method of the Model it returns non null value. Default vaue of $id should not be null or if it is null it should not query the database and return null

/**
	 * Fetches the row of database from $this->table with a primary key
	 * matching $id.
	 *
	 * @param mixed|array|null $id One primary key or an array of primary keys
	 *
	 * @return array|object|null    The resulting row of data, or null.
	 */
	public function find($id = null)
	{
		$builder = $this->builder();

CodeIgniter 4 version
v4.0.0-rc.2.1

Affected module(s)
SYSTEMPATH/Model.php at line 354

Expected behavior, and steps to reproduce if appropriate
Should return null when $id is null

Context

• OS: Ubuntu 16
• Web server Apache/2.4.18
• PHP version 7.3.9-1+ubuntu16.04.1+deb.sury.org+1

[lonnieezell]

In this case this is the desired behavior since this method can also be used as part of chaining together commands that could include where's, etc. In that case, it could actually return results.

There was a big long discussion about this and other methods a year or so back and it was done this way for consistency with other core methods.