Template changes not reflected after re-generating the site

When I run `grunt documentjs` the template files seem to be built and stored in `node_modules/documentjs/site/static` and `node_modules/documentjs/site/templates` creating multiple folders with names like `75a21ea334caf26fc57508f75c447391`

However, when I make changes to my own template files in `/styles/theme/templates/layout.mustache` (for example) and generate the site again, the changes are often not reflected in the generated site. I must manually delete all the files in `node_modules/documentjs/site/templates` and generate the site in order to see my changes.

I would expect `grunt documentjs` to automatically build the templates again instead of relying on the previous build.