ensure all index.md pages do not have "pages.md" or "index.md"

[njr2128]

As part of work started in #33, some listings in the index.md pages include "pages.md" and "index.md" but these were not fieldnotes pages created by students and are instead working files generated as part of the indexing work.

All index.md pages should be reviewed (as part of #49), and this work should include checking for the inclusion of these pages. If they are included, they should be removed.