Add authenticated privacy request route

[sanders41]

Closes #1748

Code Changes

• Created a function to facilitate both authenticated an unauthenticated privacy requests
• Created a route for authenticated privacy requests
• Added a config option to specify the parent server user name and password

Steps to Confirm

• Add parent_server_username and parent_server_password to the fides.toml file.
• login with provided credentials to get the authorization token.
• use curl to verify an authenticated request can be sent.

curl --location --request POST 'http://0.0.0.0:8080/api/v1/privacy-request/authenticated' -H 'Content-Type: application/json' --data-raw '[{"identity": {"phone_number": "+19198675309"}, "policy_key": "default_access_policy"}]' -H "Authorization: Bearer {token}"

Pre-Merge Checklist

• All CI Pipelines Succeeded
• Documentation Updated:
  • documentation complete, or draft/outline provided (tag docs-team to complete/review on this branch)
  • documentation issue created (tag docs-team to complete issue separately)
• Issue Requirements are Met
• Relevant Follow-Up Issues Created
• Update CHANGELOG.md

Description Of Changes

Write some things here about the changes and any potential caveats

[adamsachs]

nice work, this all looks really good!

just one minor comment on a merge discrepancy that we should fix up. since you're on PTO and would like to get unblocked, i'm gonna make that change myself and hopefully then can just get this merged.

[adamsachs]

all looks good to me now!