Fix v1.12 archive build (#1496)
Fix v1.12 archive build (#1496)

Add the v1.12 archive directory to `keep_files` to
prevent Jekyll from removing the directory when
building the main docs.

Signed-off-by: Sebastiaan van Stijn <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@gone.nl>
joeuo/docker.github.io,phiroict/docker,johnstep/docker.github.io,shubheksha/docker.github.io,shubheksha/docker.github.io,shin-/docker.github.io,shubheksha/docker.github.io,londoncalling/docker.github.io,anweiss/docker.github.io,bdwill/docker.github.io,joaofnfernandes/docker.github.io,shin-/docker.github.io,JimGalasyn/docker.github.io,joeuo/docker.github.io,shin-/docker.github.io,londoncalling/docker.github.io,joaofnfernandes/docker.github.io,docker/docker.github.io,LuisBosquez/docker.github.io,LuisBosquez/docker.github.io,anweiss/docker.github.io,bdwill/docker.github.io,docker/docker.github.io,joaofnfernandes/docker.github.io,joeuo/docker.github.io,johnstep/docker.github.io,joaofnfernandes/docker.github.io,londoncalling/docker.github.io,docker-zh/docker.github.io,LuisBosquez/docker.github.io,thaJeztah/docker.github.io,shubheksha/docker.github.io,LuisBosquez/docker.github.io,phiroict/docker,thaJeztah/docker.github.io,LuisBosquez/docker.github.io,JimGalasyn/docker.github.io,anweiss/docker.github.io,docker/docker.github.io,bdwill/docker.github.io,docker-zh/docker.github.io,joeuo/docker.github.io,docker/docker.github.io,JimGalasyn/docker.github.io,johnstep/docker.github.io,thaJeztah/docker.github.io,joaofnfernandes/docker.github.io,docker/docker.github.io,thaJeztah/docker.github.io,phiroict/docker,docker-zh/docker.github.io,shubheksha/docker.github.io,bdwill/docker.github.io,anweiss/docker.github.io,phiroict/docker,johnstep/docker.github.io,londoncalling/docker.github.io,phiroict/docker,shin-/docker.github.io,JimGalasyn/docker.github.io,docker-zh/docker.github.io,londoncalling/docker.github.io,thaJeztah/docker.github.io,shin-/docker.github.io,JimGalasyn/docker.github.io,johnstep/docker.github.io,bdwill/docker.github.io,joeuo/docker.github.io,docker-zh/docker.github.io,anweiss/docker.github.io