[core] our OS information in user-agent header value should be after runtime, not as a product of its own #36383
Description
Currently our value looks like
"azsdk-js-azure-storage-blob/12.28.0 core-rest-pipeline/1.22.0 Node/22.20.0 OS/(x64-Windows_NT-10.0.26100)"
which is not valid because per RFC 9110 parenthesis are used to denote comments and valid User-Agent format is
User-Agent = product *( RWS ( product / comment ) )
product = token ["/" product-version]
product-version = token
For example, in an example of browser User-Agent header, the OS info is put in comment of "Mozilla/5.0".
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/141.0.0.0 Safari/537.36 Edg/141.0.0.0
The proper place for our os information is probably in a comment for Node