Reorder columns in markdown tables: prioritize stability and req levels

[lmolkova]

Discussed during SemConv call on 9/29:

Currently the order of columns is Attribute Name -> Type -> Brief -> Examples -> Req Level -> Stability. E.g.

Attribute	Type	Description	Examples	Requirement Level	Stability
http.request.method	string	HTTP request method. [1]	GET; POST; HEAD	Required

The end users, instrumentation authors and backends probably care more about req levels and stability more than other things.

What if we did something like

Attribute	Requirement Level	Type	Description	Examples
http.request.method	Required	string	HTTP request method. [1]	GET; POST; HEAD

(we can also have multiple badges or multi-part badges)