Setup testnet tests - Closes #925

[ginacontrino]

What was the problem?

We had no configuration for running tests with testnet

How did I fix it?

• Added scripts so we can run some of the existing voting and sending tests with testnet

How to test it?

Before you run the tests, you should save the passphrase in your env
export TESTNET_PASSPHRASE='recipe bomb asset salon coil symbol tiger engine assist pact pumpkin visit'

• Then, in order to just run tests with testnet you can go:
  npm run e2e-test -- --disableChecks --cucumberOpts.tags=@testnet --params.network=testnet --params.useTestnetPassphrase=true

• In order to run tests with the custom node "https://testnet.lisk.io" you can go:
  npm run e2e-test -- --disableChecks --cucumberOpts.tags=@testnet -- --params.liskCoreURL=https://testnet.lisk.io --params.useTestnetPassphrase=true

• Make also sure that the normal tests still work:
  npm run e2e-test

Review checklist

• The PR solves E2e test send on testnet #925
• All new code follows best practices

[fchavant]

You need to move this withCredentials statement to wrap the whole sh above, i.e. you need to have:

withCredentials([...]) {
    sh '''
        [...]
        npm run --silent e2e-test:testnet:custom -- --params.baseURL file://$WORKSPACE/app/build/index.html --params.liskCoreURL http://127.0.0.1:400$N  --params.testnetPassphrase $TESTNET_PASSPHRASE --params.testnetCustomNode true
        [...]
    '''
}
[...]

[slaweet]

Good job Gina