docs: link to build ref page for --call and --check ref with bake

[crazy-max]

follow-up

• docs: reference description for --call and --check #2562
• bake: add call methods support and printing #2556

[tonistiigi]

#29 [validate-upstream 5/5] RUN htmltest
#29 0.065 htmltest started at 05:50:55 on public
#29 0.065 ========================================================================
#29 2.409 reference/cli/docker/buildx/bake/index.html
#29 2.409   hash does not exist --- reference/cli/docker/buildx/bake/index.html --> /reference/cli/docker/buildx/build/#a-namecalla-invoke-a-frontend-method---call
#29 2.409   hash does not exist --- reference/cli/docker/buildx/bake/index.html --> /reference/cli/docker/buildx/build/#a-namechecka-call-check---check
#29 2.409 reference/cli/docker/buildx_bake/index.html
#29 3.713   hash does not exist --- reference/cli/docker/buildx_bake/index.html --> /reference/cli/docker/buildx/build/#a-namecalla-invoke-a-frontend-method---call
#29 3.713   hash does not exist --- reference/cli/docker/buildx_bake/index.html --> /reference/cli/docker/buildx/build/#a-namechecka-call-check---check
#29 3.713 ========================================================================
#29 13.63 ✘✘✘ failed in 13.564807227s
#29 13.63 4 errors in 2506 documents
#29 13.63 
#29 ERROR: process "/bin/sh -c htmltest" did not complete successfully: exit code: 1
------
 > [validate-upstream 5/5] RUN htmltest:
13.63