php7 warning: sprintf Too few arguments in template-tags.php on line 30

Dear,

My apache2 server error logs receive sometimes 10 lines a minute with the following php7 warning content:
<...> HP Warning: sprintf(): Too few arguments in <MY_ROOT>/wp-content/themes/alyssas-blog/ripplethemes/template-tags.php on line 30

While this is just a warning, this is using a lot of logs space and attention.

Would it be possible to replace the following code in template-tags.php :

		$posted_on = sprintf(
			/* translators: %s: post date. */
			'<a href="' . esc_url( get_permalink() ) . '" rel="bookmark">' . $time_string . '</a>'
		);

by either this:

		$posted_on =
			'<a href="' . esc_url( get_permalink() ) . '" rel="bookmark">' . $time_string . '</a>';

or this:

		$posted_on = sprintf(
			'%s',
			'<a href="' . esc_url( get_permalink() ) . '" rel="bookmark">' . $time_string . '</a>'
		);

or this:

		$posted_on = sprintf(
			/* translators: %s: post date. */
			esc_html_x('%s', 'post author', 'alyssas-blog'),
			'<a href="' . esc_url( get_permalink() ) . '" rel="bookmark">' . $time_string . '</a>'
		);

or any other solution please?

If this is not possible or not a good idea, sorry for the inconvenience.

Best regards.

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