Task/CDF-565 Querying example returns no results

[mo-AlexFord]

JIRA: CDF-565 Description: Fix the sparql query example shown on the population guidance page

Tasks:

• [x] Updated Spaql example in HTML & JS
• [x] Updated page to reflect new query

Live preview : https://mike.dev.wmo.reference.metoffice.cloud/ui/about/querying