public DocWriter openHeading(String content, String linkId) {
        return writeAnchor(linkId).openHeading(content);
    }
Writes a heading with the given content and linkId.

<p>{@link #closeHeading} will be called to enable cleaning up any resources or
context this method creates.

@param content A string to use as the heading content.
@param linkId The identifier used to link to the heading.
@return returns the writer.
smithy-docgen/src/main/java/software/amazon/smithy/docgen/writers/DocWriter.java