Ionic Karma Assets Loading

In karma config file,there is a pattern to load css files while making unit tests which doest not load the external files in the html ie:<link href="…css".
Here is the pattern: {pattern: ‘…/src/assets/css/*.css’, watched: true, included: false, served: true, nocache: false}

When running the unit tests using npm test our config pattern not getting any error which is true.
When debugging from karma browser using chrome it does not load the css files.However when I add / in front of the link href=’/assets in the html file it is working but when I run ionic serve the file which has / in front of the link href=’/assets my icons has gone.

What I understand is that I have to put that / in front of the link href=’/assets and I have to use that pattern mentioned above.What was the reason of my icons in the html file is deleted?