docs: specify order preference for FROM
When multiple files are specified buildah considers `FROM` instruction
from the last file specified and so does `buildkit` and `docker` so lets
specify that in docs.
[NO NEW TESTS NEEDED]
[NO TESTS NEEDED]
Similar to:
@@ -255,7 +255,7 @@ option.
Specifies a Containerfile which contains instructions for building the image,
either a local file or an **http** or **https** URL. If more than one
Containerfile is specified, *FROM* instructions will only be accepted from the
-first specified file.
+last specified file.
If a build context is not specified, and at least one Containerfile is a
local file, the directory in which it resides will be used as the build
