make txp default slug for mozAddonManager (#3729)
make txp default slug for mozAddonManager (#3729)


flodolo/testpilot,flodolo/testpilot,mozilla/idea-town,flodolo/testpilot,lmorchard/idea-town-server,mozilla/idea-town-server,lmorchard/testpilot,lmorchard/testpilot,lmorchard/idea-town-server,mozilla/idea-town,flodolo/testpilot,lmorchard/testpilot,meandavejustice/testpilot,mozilla/idea-town,mozilla/idea-town-server,lmorchard/idea-town-server,lmorchard/idea-town,mozilla/idea-town-server,lmorchard/idea-town,lmorchard/testpilot,lmorchard/idea-town,meandavejustice/testpilot,meandavejustice/testpilot,mozilla/idea-town,lmorchard/idea-town,meandavejustice/testpilot,mozilla/idea-town-server,lmorchard/idea-town-server