internal/pkg: encode checksum in ident

This also rearranges the ident ir to be more predictable, and avoids an obvious and somewhat easy to get into inconsistent state.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/pkg/testdata/main.go

@@ -142,12 +142,12 @@ func main() {
 	}
 
 	const checksumEmptyDir = "MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU"
-	ident := "U2cbgVgEtjfRuvHfE1cQnZ3t8yoexULQyo_VLgvxAVJSsobMcNaFIsuDWtmt7kzK"
+	ident := "LRxdkRYNKnZT6bKiu5W8ATeAAmq3n_5AAJkF6G0EpAOEloiZvADJBkfixgtgF1Z9"
 	log.Println(m)
 	next := func() { m = m.Next; log.Println(m) }
 
 	if overlayRoot {
-		ident = "5ey2wpmMpj483YYa7ZZQciYLA2cx3_l167JCqWW4Pd-5DVp81dj9EsBtVTwYptF6"
+		ident = "UB9HPeMgMPJf3Ut4jLWwnCtu_P3Lr29i8Erf084bHe8jjzBMKPDNxQ3RMrirkH6H"
 
 		if m.Root != "/" || m.Target != "/" ||
 			m.Source != "overlay" || m.FsType != "overlay" {
@@ -165,7 +165,7 @@ func main() {
 				log.Fatal("unexpected artifact checksum")
 			}
 		} else {
-			ident = "tfjrsVuBuFgzWgwz-yPppFtylYuC1VFWnKhyBiHbWTGkyz8lt7Ee9QXWaIHPXs4x"
+			ident = "g6gj2JWNXN-oNikou626vDqcMeZCn_TcV4xKuizBaPAWcasG2sVvItb5kZovMrzE"
 
 			lowerdirsEscaped := strings.Split(lowerdir, ":")
 			lowerdirs := lowerdirsEscaped[:0]
@@ -194,7 +194,7 @@ func main() {
 		}
 	} else {
 		if hostNet {
-			ident = "QdsJhGgnk5N2xdUNGcndXQxFKifxf1V_2t9X8CQ-pDcg24x6mGJC_BiLfGbs6Qml"
+			ident = "TAspufRsG2I_TsxUUj2b7bUnCHgcVSdh6aOZpzL0W5Bjn4EZmOGzjofaOWd8J11H"
 		}
 
 		if m.Root != "/sysroot" || m.Target != "/" {
@@ -213,14 +213,14 @@ func main() {
 	}
 
 	if promote {
-		ident = "O-6VjlIUxc4PYLf5v35uhIeL8kkYCbHYklqlmDjFPXe0m4j6GkUDg5qwTzBRESnf"
+		ident = "ywzI31S5McuYu7vzI2kqpSC_nsNzpWBXVCwPoLAYi9QVT0mODgzqoo9jYYaczPbf"
 	}
 
 	next() // testtool artifact
 
 	next()
 	if overlayWork {
-		ident = "acaDzHZv40dZaz4cGAXayqbRMgbEOuiuiUijZL8IgDQvyeCNMFE3onBMYfny-kXA"
+		ident = "Fud5ldJfpsgLt-rkLWrLO-aVYhQm-esTswetjxydPeQMK4jHNJ_1fGHVahaiCZ9y"
 		if m.Root != "/" || m.Target != "/work" ||
 			m.Source != "overlay" || m.FsType != "overlay" {
 			log.Fatal("unexpected work mount entry")