docs: fix and update scoped configuration example (#7742)

The [Auth related
configuration](https://docs.npmjs.com/cli/v10/configuring-npm/npmrc#auth-related-configuration)
docs contains a mistakenly commented configuration line.
This PR makes the scope examples more clear by adding newlines and
uncomment the valid configuration line.

Author: demedos

docs/lib/content/configuring-npm/npmrc.md

@@ -120,10 +120,13 @@ _authToken=MYTOKEN
 @myorg:registry=https://somewhere-else.com/myorg
 @another:registry=https://somewhere-else.com/another
 //registry.npmjs.org/:_authToken=MYTOKEN
+
 ; would apply to both @myorg and @another
-; //somewhere-else.com/:_authToken=MYTOKEN
+//somewhere-else.com/:_authToken=MYTOKEN
+
 ; would apply only to @myorg
 //somewhere-else.com/myorg/:_authToken=MYTOKEN1
+
 ; would apply only to @another
 //somewhere-else.com/another/:_authToken=MYTOKEN2
 ```