Implement template build tests

[dappnodedev]

We need to test the functionality of building packages in a unified repository. In order to do this, we might need to implement something similar to: https://github.com/dappnode/DAppNodeSDK/blob/master/test/commands/build.test.ts

In case that the test is implemented in the same way, this issue depends on: https://github.com/orgs/dappnode/projects/69/views/1?pane=issue&itemId=56023066