vendor: update buildkit v0.14-dev version 549891b

Brings in formatter for lint requests.

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

vendor/github.com/moby/buildkit/frontend/dockerfile/command/command.go

@@ -0,0 +1,46 @@
+// Package command contains the set of Dockerfile commands.
+package command
+
+// Define constants for the command strings
+const (
+	Add         = "add"
+	Arg         = "arg"
+	Cmd         = "cmd"
+	Copy        = "copy"
+	Entrypoint  = "entrypoint"
+	Env         = "env"
+	Expose      = "expose"
+	From        = "from"
+	Healthcheck = "healthcheck"
+	Label       = "label"
+	Maintainer  = "maintainer"
+	Onbuild     = "onbuild"
+	Run         = "run"
+	Shell       = "shell"
+	StopSignal  = "stopsignal"
+	User        = "user"
+	Volume      = "volume"
+	Workdir     = "workdir"
+)
+
+// Commands is list of all Dockerfile commands
+var Commands = map[string]struct{}{
+	Add:         {},
+	Arg:         {},
+	Cmd:         {},
+	Copy:        {},
+	Entrypoint:  {},
+	Env:         {},
+	Expose:      {},
+	From:        {},
+	Healthcheck: {},
+	Label:       {},
+	Maintainer:  {},
+	Onbuild:     {},
+	Run:         {},
+	Shell:       {},
+	StopSignal:  {},
+	User:        {},
+	Volume:      {},
+	Workdir:     {},
+}