EmrEtlRunner: update Contracts for get_failure_details

[benjben]

After R114 there has been incidents with no information about steps in stdout and a strange message in stderr:

D, [2019-05-22T01:53:38.127314 #19595] DEBUG -- : Initializing EMR jobflow
D, [2019-05-22T01:54:11.897148 #19595] DEBUG -- : EMR jobflow j-41TJT0JDLH5H started, waiting for jobflow to complete...
I, [2019-05-22T01:56:13.054432 #19595] INFO -- : No RDB Loader logs

...
ArgumentError: wrong number of arguments (2 for 1)
failure_callback at uri:classloader:/emr-etl-runner/lib/snowplow-emr-etl-runner/contracts.rb:786
block in redefine_method at uri:classloader:/gems/contracts-0.11.0/lib/contracts/method_handler.rb:143
run at uri:classloader:/emr-etl-runner/lib/snowplow-emr-etl-runner/emr_job.rb:786
send_to at uri:classloader:/gems/contracts-0.11.0/lib/contracts/method_reference.rb:43
call_with at uri:classloader:/gems/contracts-0.11.0/lib/contracts/call_with.rb:76
block in redefine_method at uri:classloader:/gems/contracts-0.11.0/lib/contracts/method_handler.rb:138
run at uri:classloader:/emr-etl-runner/lib/snowplow-emr-etl-runner/runner.rb:138
send_to at uri:classloader:/gems/contracts-0.11.0/lib/contracts/method_reference.rb:43
call_with at uri:classloader:/gems/contracts-0.11.0/lib/contracts/call_with.rb:76
block in redefine_method at uri:classloader:/gems/contracts-0.11.0/lib/contracts/method_handler.rb:138
<main> at uri:classloader:/emr-etl-runner/bin/snowplow-emr-etl-runner:41
load at org/jruby/RubyKernel.java:994
<main> at uri:classloader:/META-INF/main.rb:1
require at org/jruby/RubyKernel.java:970
(root) at uri:classloader:/META-INF/main.rb:1
<main> at uri:classloader:/META-INF/jruby.home/lib/ruby/stdlib/rubygems/core_ext/kernel_require.rb:1
ERROR: org.jruby.embed.EvalFailedException: (ArgumentError) wrong number of arguments (2 for 1)

Problem with Ruby Contracts there:

Contract String => String
def get_failure_details(jobflow_id, cluster_status, cluster_step_status_for_run)