[SDK-1534] Move "source" to top level for v1/url requests

[nsingh-branch]

Reference

SDK-1534 -- Move 'source' to top level for v1/url

Description

Originally, v1/url requests had source: android nested inside the data object. However, iOS has always sent source at the top level. This change updates the Android SDK's behavior to be like the iOS SDK's by moving source to the top level of v1/url requests.

The old methods that added source were also removed in this change. generateLongUrlWithParams() was also updated slightly to fix tests and to be more like getShortUrl().

Testing Instructions

Create a short URL to send a v1/url request and note that source has moved from being within data to at the top level.

Previous Request

{
  "tags": [],
  "alias": "",
   ...
  "data": {
    "custom": "data",
    "source": "android",  //Inside data{}
  },
}

New Request

{
  "tags": [],
  "alias": "",
  "source": "android",  //Moved to outside data{}
   ...
  "data": {
    "custom": "data",
  },
}

Risk Assessment [LOW]

• [ ] I, the PR creator, have tested — integration, unit, or otherwise — this code.

Reviewer Checklist (To be checked off by the reviewer only)

• [ ] JIRA Ticket is referenced in PR title.
• Correctness & Style
  • [ ] Conforms to AOSP Style Guides
  • [ ] Mission critical pieces are documented in code and out of code as needed.
• [ ] Unit Tests reviewed and test issue sufficiently.
• [ ] Functionality was reviewed in QA independently by another engineer on the team.