subscription-manager subscribe --pool fails with 'undefined method `closed?' for #<PhusionPassenger::Utils::TeeInput:0x0000000efc93e8>' on passenger 4.0.18 + rest-client 1.6.7
The issue is we pass raw request body that we get from the rails and pass directly to the rest client. Unfortunately, the interface is not the same
Fixes #5715 - make sure the rest client doesn't get PhusionPassenger::Utils::TeeInput
Rest client 1.6.7 is not able to handle that, passing the string
instead. The behavior should stay the same.