[ti_google_threat_intelligence] Promote package to GA after resolving pending issues

[niraj-crest]

We would like to track the readiness for promoting the ti_google_threat_intelligence package to GA.

The following issues and enhancements need to be resolved before GA can be considered:

• [ti_google_threat_intelligence] Remove manual pipeline and field mappings once pipeline-transform dependency handling is supported #14286
• [Change Proposal] Add support for ingest pipelines in transforms package-spec#833
• Source Index Queries in Transform not Applied During System Tests elastic-package#2676

Relates

• [Google Threat Intelligence] Add Integration Package #13189