context: fix copypasta in the docs

Fix wrong comment, likely due to trivial copy/paste mistake.
No code changes.

Signed-off-by: Francesco Romani <fromani@redhat.com>

pkg/context/context.go

@@ -51,7 +51,7 @@ func New(opts ...*option.Option) *Context {
 	return ctx
 }
 
-// FromEnv returns an Option that has been populated from the environs or
+// FromEnv returns a Context that has been populated from the environs or
 // default options values
 func FromEnv() *Context {
 	chrootVal := option.EnvOrDefaultChroot()