docker ps: always use --quiet, also combined with --format

Previously, the formatter would ignore the quiet option if a custom format
was passed; this situation was handled in runPs(), where custom formats
would only be applied if the quiet option was not set, but only if the
format was set in the CLI's config.

This patch updates NewContainerFormat() to do the same, even if a `--format`
was passed on the command-line.

This is a change in behavior, so may need some discussion; possible alternatives;

- produce an error if both `--format` and `--quiet` are passed
- print a warning if both are passed (but use the logic from this patch)

Before this patch:

```console
docker ps --format '{{.Image}}'
ubuntu:22.04
alpine

docker ps --format '{{.Image}}' --quiet
ubuntu:22.04
alpine

mkdir -p ~/.docker/
echo '{"psFormat": "{{.Image}}"}' > ~/.docker/config.json

docker ps
ubuntu:22.04
alpine

docker ps --quiet
ubuntu:22.04
alpine
```

With this patch applied:

```console
docker ps --format '{{.Image}}'
ubuntu:22.04
alpine

docker ps --format '{{.Image}}' --quiet
40111f61d5c5
482efdf39fac

mkdir -p ~/.docker/
echo '{"psFormat": "{{.Image}}"}' > ~/.docker/config.json

docker ps
ubuntu:22.04
alpine

docker ps --quiet
40111f61d5c5
482efdf39fac
```

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

cli/command/container/list_test.go

@@ -309,8 +309,21 @@ func TestContainerListWithFormat(t *testing.T) {
 			}, nil
 		},
 	})
-	cmd := newListCommand(cli)
-	cmd.Flags().Set("format", "{{ .Names }} {{ .Image }} {{ .Labels }}")
-	assert.NilError(t, cmd.Execute())
-	golden.Assert(t, cli.OutBuffer().String(), "container-list-with-format.golden")
+
+	t.Run("with format", func(t *testing.T) {
+		cli.OutBuffer().Reset()
+		cmd := newListCommand(cli)
+		assert.Check(t, cmd.Flags().Set("format", "{{ .Names }} {{ .Image }} {{ .Labels }}"))
+		assert.NilError(t, cmd.Execute())
+		golden.Assert(t, cli.OutBuffer().String(), "container-list-with-format.golden")
+	})
+
+	t.Run("with format and quiet", func(t *testing.T) {
+		cli.OutBuffer().Reset()
+		cmd := newListCommand(cli)
+		assert.Check(t, cmd.Flags().Set("format", "{{ .Names }} {{ .Image }} {{ .Labels }}"))
+		assert.Check(t, cmd.Flags().Set("quiet", "true"))
+		assert.NilError(t, cmd.Execute())
+		golden.Assert(t, cli.OutBuffer().String(), "container-list-quiet.golden")
+	})
 }

cli/command/container/testdata/container-list-quiet.golden

@@ -0,0 +1,2 @@
+container_id
+container_id

cli/command/formatter/container.go

@@ -55,6 +55,9 @@ ports: {{- pad .Ports 1 0}}
 		}
 		return Format(format)
 	default: // custom format
+		if quiet {
+			return DefaultQuietFormat
+		}
 		return Format(source)
 	}
 }

cli/command/formatter/container_test.go

@@ -163,7 +163,7 @@ containerID2   ubuntu    ""        24 hours ago                       foobar_bar
 		},
 		{
 			Context{Format: NewContainerFormat("table {{.Image}}", true, false)},
-			"IMAGE\nubuntu\nubuntu\n",
+			"containerID1\ncontainerID2\n",
 		},
 		{
 			Context{Format: NewContainerFormat("table", true, false)},