public static Content fromString(String text) {
    return fromStringWithRole(DEFAULT_ROLE, text);
  }
Creates a content from a string, assuming the role is "user".

<p>The resulting content will contain one single {@link com.google.cloud.vertexai.api.Part}
with its text field set.

<p>To create a text content for "model", use `ContentMaker.forRole("model").fromString(text);
java-vertexai/google-cloud-vertexai/src/main/java/com/google/cloud/vertexai/generativeai/ContentMaker.java