Re-enable CLI Download e2e tests

[richard-cox]

• head points to 2.10.0 cli binaries, which aren't available
  • at time of issue creation v2.10-head points at 2.9.0 binaries which are available
• this causes are e2e tests that check links (amongst other things) to 404
• so now we check for 404 and need to change back to 200 when the binaries are there

[richard-cox]

/backport v2.10.1

[mantis-toboggan-md]

head builds now use a 2.11 CLI images that are downloading successfully. I'm rolling this issue into this pr #12587

It is worth noting that the release-2.10 branch, which uses a 2.10 CLI version, is still returning 404s