feat(firebaseml): update the api

#### firebaseml:v2beta

The following keys were deleted:
- schemas.GoogleCloudAiplatformV1beta1GroundingAttribution (Total Keys: 17)
- schemas.GoogleCloudAiplatformV1beta1GroundingMetadata.properties.groundingAttributions (Total Keys: 2)

The following keys were added:
- schemas.GoogleCloudAiplatformV1beta1Candidate.properties.score (Total Keys: 3)
- schemas.GoogleCloudAiplatformV1beta1CountTokensRequest.properties.systemInstruction.$ref (Total Keys: 1)
- schemas.GoogleCloudAiplatformV1beta1CountTokensRequest.properties.tools (Total Keys: 2)

Author: yoshi-automation