Add ttd/thetradedesk alias

[andre-gielow-ttd]

🔧 Type of changes

• new bid adapter
• bid adapter update
• new feature
• new analytics adapter
• new module
• module update
• bugfix
• documentation
• configuration
• dependency update
• tech debt (test coverage, refactorings, etc.)

✨ What's the context?

Allow integration to be done to The Trade Desk using either thetradedesk or ttd bidder code through an alias.

🧠 Rationale behind the change

Prebid.js uses ttd bidder code while PBS uses thetradedesk. Allow both to have a seamless experience.

🔎 New Bid Adapter Checklist

• verify email contact works
• NO fully dynamic hostnames
• geographic host parameters are NOT required
• direct use of HTTP is prohibited - implement an existing Bidder interface that will do all the job
• if the ORTB is just forwarded to the endpoint, use the generic adapter - define the new adapter as the alias of the generic adapter
• cover an adapter configuration with an integration test

🧪 Test plan

Already tested by Magnite locally.

🏎 Quality check

• Are your changes following our code style guidelines?
• Are there any breaking changes in your code?
• Does your test coverage exceed 90%?
• Are there any erroneous console logs, debuggers or leftover code in your changes?

[Net-burst]

LGTM

[Net-burst]

PBS-Go counterpart: prebid/prebid-server#4357