ci(vertexai): remove specific token count test

[glasnt]

Description

Addresses #10129

This check is currently failing with expected: 16252 but was: 16708.

I don't think checking the specific amount of tokens used is useful, as I don't believe this number would be a constant as we continue to update the version of Gemini used for these tests.

Python and Golang might have comments (py, go on the amount of tokens, but the tests just confirm the function completed, not the output (py, go).

I've adjusted the tests to be less strict.

Checklist

• I have followed Sample Format Guide
• pom.xml parent set to latest shared-configuration
• Appropriate changes to README are included in PR
• These samples need a new API enabled in testing projects to pass (let us know which ones)
• These samples need a new/updated env vars in testing projects set to pass (let us know which ones)
• Tests pass: mvn clean verify required
• Lint passes: mvn -P lint checkstyle:check required
• Static Analysis: mvn -P lint clean compile pmd:cpd-check spotbugs:check advisory only
• This sample adds a new sample directory, and I updated the CODEOWNERS file with the codeowners for this sample
• This sample adds a new Product API, and I updated the Blunderbuss issue/PR auto-assigner with the codeowners for this sample
• Please merge this PR for me once it is approved