Fix content docstring
Documentation, Easy Fix
"0 or more" is incorrect. Each FileContent is exactly 1 file.
Once this is fixed in the file plugin, please update the plugin writer's guide as well where we use the FileContent as an example in (at least) 2 places.
Fix FileContent description in docs
File content is always 1 file. Fixed in models docstring.
re: #4372 https://pulp.plan.io/issues/4372
Required PR: https://github.com/pulp/pulpcore-plugin/pull/61
Signed-off-by: Pavel Picka email@example.com