Remove trailing slash from request to retrieve all tags

[schwartzie]

Calls to Manager.get_all_tags() started throwing a NotFoundError for me.

I turned on logging and confirmed that the call to https://api.digitalocean.com/v2/tags/?per_page=200 is returning a 404. I validated this by directly submitting the request:

$ curl "https://api.digitalocean.com/v2/tags/?per_page=200" \ 
   -H "Authorization: Bearer <token>"
{"error":"route not found","root_causes":[]}

Removing the trailing slash from the request returned the expected response object both in curl and through the library.

This is also consistent with the API documentation:

To list all of your tags, you can send a GET request to /v2/tags.

[koalalorenzo]

I am not sure why the tests are failing, could you update them in case those keep failing?

[schwartzie]

It looks like the request being made in the test to validate the library's output had the same problem with the trailing slash. I've pushed an update to the test as well now.