core-common: add AttributeKey.Make

[iRevive]

The PR is based on #911.

Motivation

Many codebases utilize newtype/opaque types for type safety. When converted to attributes, some entities must always use the same name.

With Attribute.Make the conversion process can be simplified.

---

Example

The model definition:

case class UserId(id: Int)

object UserId {
  implicit val userIdFocus: AttributeKey.Focus[UserId, Long] =
    _.id.toLong
    
  implicit val userIdAttribute: Attribute.Make[UserId] =
    Attribute.Make.named("user.id")
}

Before

def findUser(userId: UserId): F[Unit] = 
  Tracer[F].span("findUser", Attribute("user.id", userId.id.toLong))

After

def findUser(userId: UserId): F[Unit] = 
  Tracer[F].span("findUser", userId)

[iRevive]

The implicit conversion happens here.