op: opening url paths that end in a file name gives a 404

[apolopena]

Describe the bug

op info.php
opens in preview browser:
https://8002-rose-coyote-jfbssmea.ws-us04.gitpod.io/info.php/
The trailing slash that op appends makes the server return a 404 error
while
https://8002-rose-coyote-jfbssmea.ws-us04.gitpod.io/info.php
will display the info.php page as it should

Steps to reproduce

op index.php

Notice the url ends with a trailing slash which gives a 404 error

Expected behavior

op index.php should open the home page in the preview browser just like op with no arguments does
url paths ending in file name or a file name with query params should not display a 404 when opening with the op command

Additional information

the op command is an alias that uses .gb/bash/open-preview.sh

[apolopena]

related to #131