Add IoT Developer Survey Banner to Sparkplug.eclipse.org

Created by: GraehamHui

Please add the following banner to the sparkplug.eclipse.org website

Banner:

Link: https://www.surveymonkey.com/r/NSLQWF2 The ad should run from May 11 to June 26 EOD

Please let me know if there's any other info you need.

CC: @Ioana240