set up auto import of metrics pages

This one is likely to be the most difficult since I'm told the metrics definitions are spread across several repos/live with each of the WGs that developed them.

These pages are part of the knowledgebase part of the wordpress site too so their content hasn't yet been imported into Hugo.

No files or tests are named. Start by mapping where the metrics definitions live across the referenced repositories and working groups, then inspect how the Hugo knowledgebase currently receives content from the WordPress site. Done means the metrics pages are automatically imported into Hugo with their content preserved.

Written by the indexing model from the issue text.