[12.x] Changed whereRelation and related function to work with only two params when the …

[habibendris]

The Eloquent whereRelation accepts 4 parameters in total $relation, $column, $operator = null, $value = null

If the $column parameter is not a \Closure we should be able to use a syntax like
where clause.

If either of $column and $operator value is not null the addDotNotationToWhereRelation function
skips everything.

In where clause we can use something like this

    $posts = Post::query()
        ->where('user_id', Auth::id());
        ->where('user_id', '!=', $request->user_id);

So whenever we want to query we have to use the whereRelation as follows.

$posts = Post::query()
    ->whereRelation('comments', 'user_id', Auth::id())
    ->get()

We always have to use atleast 3 parameters.
This pull request allows us to only use 2 for this usecase.

What i want to do is the whereRelation and other related relation function
to act as the where clause.

    $posts = Post::query()
        ->whereRelation('comments', 'user_id', Auth::id());
        ->whereRelation('comments', 'user_id', '!=', $request->user_id);

    $posts = Post::query()
        ->whereRelation('comments.user_id', Auth::id());
        ->whereRelation('comments', 'user_id', '!=', $request->user_id);

This commit doesnt break any existing changes because i have written integration testing.
But if we want it to fully replace the previous method we can change the code to accomodate those things.