AK1003 - Add ReceiveAsync with sync lambda analyzer and code fix

[Arkatufus]

Partially fixes #57

Changes

Add analyzer and code fix for ReceiveAsync<T>() and ReceiveAnyAsync() invocations that does not use async lambda expression.

Notes

This implementation does not analyze ReceiveAsync<T>() and ReceiveAnyAsync() that uses a method delegate. This will need a separate analyzer.

Example:

public sealed class MyActor : ReceiveActor
{
    public MyActor()
    {
        ReceiveAsync<string>(Handler); // This can't be analyzed, for now.
    }
    
    private async Task Handler(string s) { }
}

Code fixes

ReceiveAsync with async keyword and no await keywords

ReceiveAsync<string>(async str =>
{
    Sender.Tell(str);
});

to

Receive<string>(str =>
{
    Sender.Tell(str);
});

ReceiveAnyAsync with async keyword and no await keywords

ReceiveAnyAsync(async o =>
{
    Sender.Tell(o);
});

to

ReceiveAny(o =>
{
    Sender.Tell(o);
});

ReceiveAsync with no body block with async keyword and no await keywords

ReceiveAsync<string>(async str => Sender.Tell(str));

to

Receive<string>(str => Sender.Tell(str));

ReceiveAnyAsync with no body block with async keyword and no await keywords

ReceiveAnyAsync(async o => Sender.Tell(o));

to

ReceiveAny(o => Sender.Tell(o));

[Aaronontheweb]

Just left one question for you @Arkatufus

[Aaronontheweb]

LGTM