I tried it like this, however it still adds group claims in the access token:

export const getDatabricksToken = async () => {
    const account = msalInstance.getActiveAccount();
    const response = await msalInstance.acquireTokenSilent({
        scopes: ["2ff814a6-3304-4ab8-85cb-cd0e6f879c1d/user_impersonation"],
        account: account,
        claims: JSON.stringify({
            "access_token": {
                "groups": null
            }
        })        
    })
    return response.accessToken
};