Connection#build_exclusive_url: replace simple syntax

[hyuraku]

Description

apply the advice about Connection#build_exclusive_url's syntax in #1349 (comment)

On a side note, the regex to check for a trailing slash here could be replaced with a simple base.path.end_with?('/') which probably is faster and more readable. Also here there's a direct call to URI.parse instead of Utils.URI(...) circumventing the custom URL parser.

Todos

List any remaining work that needs to be done, i.e:

• Tests
• Documentation

Additional Notes

Optional section

[olleolleolle]

Looks good and small!