Mention the need to update tests in docs in MAINTENANCE.md.
Mention the need to update tests in docs in MAINTENANCE.md.

internalfx/nunjucks,oddbird/nunjucks,mozilla/nunjucks,internalfx/nunjucks,devoidfury/nunjucks,mozilla/nunjucks,internalfx/nunjucks,kevinschaul/nunjucks,internalfx/nunjucks,oddbird/nunjucks,oddbird/nunjucks,oddbird/nunjucks,kevinschaul/nunjucks,mozilla/nunjucks,devoidfury/nunjucks,kevinschaul/nunjucks,kevinschaul/nunjucks,devoidfury/nunjucks