Add attribute naming checks

[lmolkova]

According to attribute naming:

semantic-conventions/docs/general/attribute-naming.md

Lines 52 to 58 in e299079

	- Names SHOULD NOT coincide with namespaces. For example if
	`service.instance.id` is an attribute name then it is no longer valid to have
	an attribute named `service.instance` because `service.instance` is already a
	namespace. Because of this rule be careful when choosing names: every existing
	name prohibits existence of an equally named namespace in the future, and vice
	versa: any existing namespace prohibits existence of an equally named
	attribute key in the future.

we SHOULD NOT allow adding attributes that would collide with namespaces (e.g. in presence of log.iostream attribute, we should not allow adding log.iostream.something_else).

But we don't have an automated check for it

Steps to Reproduce (if any)

#1067

Expected Result

There should be a check preventing adding an attribute like log.iostream.something_else in presence of existing attribute log.iostream or vice versa

Actual Result

Semconv checks are passed and attribute can be added