feat(fun/clbot,ops/machines/whitby): filter tvix-dev clbot

In #tvix-dev, we want to display only CLs that relate to tvix and
related projects.

So use a pretty dumb allow-list for which CLs to display in that
channel.

Change-Id: I3ef50b64e3d7fbc27a6690be6a10f1b55c04cd6e
Reviewed-on: https://cl.tvl.fyi/c/depot/+/11658
Reviewed-by: flokli <flokli@flokli.de>
Reviewed-by: lukegb <lukegb@tvl.fyi>
Tested-by: BuildkiteCI

fun/clbot/clbot_test.go

@@ -0,0 +1,24 @@
+package main
+
+import (
+	"testing"
+)
+
+func TestChangeShouldBeSkipped(t *testing.T) {
+	dontSkipAny := ""
+	if changeShouldBeSkipped(dontSkipAny, "mysubject") {
+		t.Fatal("dontSkipAny should not not be skip any")
+	}
+
+	showThese := "A,B"
+	if changeShouldBeSkipped(showThese, "A") {
+		t.Fatal("A should be shown")
+	}
+	if changeShouldBeSkipped(showThese, "B") {
+		t.Fatal("B should be shown")
+	}
+	if !changeShouldBeSkipped(showThese, "C") {
+		t.Fatal("C should not be shown")
+	}
+
+}