Fix reference to the TUF Key Hierarchy diagram (#5952)
Fix reference to the TUF Key Hierarchy diagram (#5952)

I'm not quite sure about how the `{:width="400px"}` attribute will be rendered, but it looks like there was a typo preventing the SVG from being rendered on https://docs.docker.com/notary/service_architecture/
anweiss/docker.github.io,docker/docker.github.io,londoncalling/docker.github.io,docker/docker.github.io,johnstep/docker.github.io,johnstep/docker.github.io,thaJeztah/docker.github.io,JimGalasyn/docker.github.io,londoncalling/docker.github.io,thaJeztah/docker.github.io,anweiss/docker.github.io,docker/docker.github.io,anweiss/docker.github.io,anweiss/docker.github.io,docker/docker.github.io,johnstep/docker.github.io,JimGalasyn/docker.github.io,johnstep/docker.github.io,johnstep/docker.github.io,londoncalling/docker.github.io,thaJeztah/docker.github.io,londoncalling/docker.github.io,JimGalasyn/docker.github.io,londoncalling/docker.github.io,thaJeztah/docker.github.io,anweiss/docker.github.io,JimGalasyn/docker.github.io,thaJeztah/docker.github.io,docker/docker.github.io,JimGalasyn/docker.github.io