Add some docs about build-arg's impact on the cache
Add some docs about build-arg's impact on the cache

Closes #18017

Signed-off-by: Doug Davis <ff3bde741799c0eff815b83a54eda3fc494df54f@us.ibm.com>

docker/cli,redpanda/cli,allencloud/cli,cpuguy83/cli,Zebrilee/cli,Zebrilee/cli,dnephin/cli,redpanda/cli,dnephin/cli,riyazdf/cli,thaJeztah/cli,e11137/cli,riyazdf/cli,cpuguy83/cli,ashfall/cli,thaJeztah/cli,allencloud/cli,docker/cli,e11137/cli,ashfall/cli