attribution on maps applies to all layers despite being set to only one

[alexarobu]

Describe the bug
I am setting the attribution on a layer like so in the config-viewer.xml:

      <ows-context:VendorExtension>
        <ows-context:Attribution>
          <ows-context:Title>© Crown copyright and database rights Ordnance Survey xxxxx</ows-context:Title>
        </ows-context:Attribution>
      </ows-context:VendorExtension>

However, this shows on all layers on the map, despite others not having the attribution set.

To Reproduce
Steps to reproduce the behavior:

1. Edit your config-viewer.xml file
2. Set up a layer and set its attribution like above
3. Set up a second layer with no attribution
4. Go to the map
5. See error by changing between the layers

Expected behavior
I was expecting the attribution to only show on the layer it's applied to, since other layers could technically have a different attribution statement or not need one at all.