Integration tests CI is failing due to a port clash in devnet tests. I
believe this is because there are 2 packages of devnet integration tests
and go can run tests from separate packages in parallel (by default it
does package level parallelism). A simple fix would be to just have all
devnet integration tests in 1 package and run all these tests
sequentially within the package (ie not use t.Parallel). This PR moves
all devnet integration tests in 1 package.
`"ContextStart devnet start failed: private api: could not create
listener: listen top 127.0.0.1:10090: bind: address already in use,
addr=localhost:10090"`
