[exporter/googlesecops] Add config fields, validation, and factory setup

[colelaven]

Description

• Adds the basic factory setup, config fields, and config validation to the Google SecOps Exporter
• Updates the README with a configuration section and some example configurations

This is part of the donation of the Google SecOps Exporter: #46148
Followup to #47132

This is the first of 2 PRs covering the 2nd step in donating a new component, the component implementation.

1. Factory setup, config fields, config validation, noop exporter
2. Full exporter implementation

Testing

Unit tests are present covering various configurations and their validation.

Documentation

The README has been updated with a configuration section describing all of the config fields and their behavior, as well as multiple example configurations for common use cases.