I have seen that there will exported template-registry as empty file:

Last test run:
https://github.com/adopted-ember-addons/ember-file-upload/actions/runs/7606502732/job/20712414961#step:4:40

Edit: found this issue on addon blueprint embroider-build/addon-blueprint#195 (comment)

Edit 2: While working on a other addon i have found out, that line is not necessary and generates the empty file. we can remove it:
https://github.com/adopted-ember-addons/ember-file-upload/blob/master/ember-file-upload/rollup.config.mjs#L27