Remove transitive vulerability to LiteLLM via upgrade of google-cloud-aiplatform

[jscheffl]

To remove potential vulnerability as google-cloud-ai-platform optionally sources litellm, upgrade dependency to google package which prevents the vulnerable version to be used.

Unfortunately I see no other way to enforce this as the transitive dependency is optional only and enforcing a specific version is only possible if we make the optional dependency mandatory.

Unfortunately the google package only upper bounds the version to the last non-vulnerable version, hoping for an improvement as litellm==1.83.0 should actually fix it.

PMC Only, see https://github.com/apache/airflow/security/dependabot/537
Google PR: googleapis/python-aiplatform#6484

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