Update for UploadUserData Improvements and Getter Operations

[RDPerera]

Summary

This PR introduces an update to the documentation to reflect the recent improvements made to the UploadUserData operation and the addition of new getter operations. The documentation has been revised to include the following changes:

1. Updated Documentation for UploadUserData:

   • Added detailed explanations on the new support for uploading user data as a JSON array.
   • Included information about the internal conversion of the JSON array into a Google Ads API UserData object.
   • Explained the normalization process for user identifiers and the supported formats (phone numbers, emails, mobile IDs, third-party user IDs, and address information).

2. Updated Documentation for Getter Operations:

   • Added a section on the new getUserLists operation, including the optional filterByName feature for filtering user lists by name.
   • Included documentation for getCustomers and getCampaigns to provide clarity on their functionality and usage.

[CLAassistant]

All committers have signed the CLA.