chore(deps): update dependency langchain-google-vertexai to v2

[renovate-bot]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
langchain-google-vertexai	==1.0.6 -> ==2.0.0

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[davidcavazos]

On Python 3.11

The conflict is caused by:
    The user requested langchain-core==0.2.11
    langchain-google-vertexai 2.0.0 depends on langchain-core<0.4 and >=0.3.0

We'll need to update langchain-core as well.

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On Python 3.8

ERROR: Could not find a version that satisfies the requirement langchain-google-vertexai==2.0.0 (from versions: 0.0.1rc0, 0.0.1, 0.0.1.post1, 0.0.2, 0.0.3, 0.0.5, 0.0.6rc0, 0.0.6, 0.0.7, 0.1.0, 0.1.1, 0.1.2, 0.1.3, 1.0.1, 1.0.2, 1.0.3, 1.0.4, 1.0.5, 1.0.6, 1.0.7, 1.0.8, 1.0.9, 1.0.10)
ERROR: No matching distribution found for langchain-google-vertexai==2.0.0

We'll need a version conditional for Python < 3.x (not sure what's the latest version supported for v2.0.0)