Fix backtrace filtering for net-ssh

Improve our filter pattern so it works for this kind of error:

SocketError: getaddrinfo: hostname nor servname provided, or not known
  /usr/local/lib/ruby/2.2/timeout.rb:74:in `timeout'
  /usr/local/lib/ruby/2.2/timeout.rb:125:in `timeout'
  /home/tj/.gem/ruby/22/gems/net-ssh-2.9.2/lib/net/ssh.rb:207:in `new'
  /home/tj/.gem/ruby/22/gems/net-ssh-2.9.2/lib/net/ssh.rb:207:in `start'

features/cli/error_reporting.feature

@@ -1,24 +1,22 @@
 Feature: CLI error reporting
 
-  Background:
-    Given a recipe with:
-      """
-      task(:trigger_error) { fail 'some error' }
-      """
-
   Scenario: reports recipe errors
+    Given a recipe with an error
     When I execute the recipe
     Then the exit status must be 70
     And the output must match /\ARuntimeError: some error\n/
 
   Scenario: reports errors with a backtrace
+    Given a recipe with an error
     When I execute the recipe
     Then the output must match /^\s+recipe\.rb:\d+:in /
 
   Scenario: prepends recipe file path in the backtrace
+    Given a recipe with an error
     When I execute the recipe
     Then the output must match /^\s+recipe\.rb \(recipe\)\n\s+recipe\.rb:/
 
   Scenario: excludes net-ssh from backtrace
+    Given a recipe using a remote
     When I execute the recipe on unknown remote target
     Then the output must not contain "net-ssh"

features/steps/recipe_steps.rb

@@ -2,6 +2,14 @@ Given /^a recipe with:$/ do |recipe_body|
   write_file 'recipe.rb', recipe_body
 end
 
+Given /^a recipe with an error$/ do
+  write_file 'recipe.rb', "task(:trigger_error) { fail 'some error' }\n"
+end
+
+Given /^a recipe using a remote$/ do
+  write_file 'recipe.rb', "task(:some_task) { sh 'echo hello' }\n"
+end
+
 Given /^a recipe named "([^"]+)" with:$/ do |recipe_path, recipe_body|
   write_file recipe_path, recipe_body
 end
@@ -16,6 +24,7 @@ end
 
 When /^I execute the recipe on unknown remote target$/ do
   run_simple 'producer recipe.rb -t #unknown_host.test', false
+  assert_matching_output '\ASocketError', all_output
 end
 
 When /^I successfully execute the recipe$/ do

lib/producer/core/error_formatter.rb

@@ -3,8 +3,8 @@ module Producer
     class ErrorFormatter
       FILTERS = [
         /\/producer-\w+\/(?:bin|lib)\//,
-        /\/net\/ssh\//,
-        /\/net\/sftp\//
+        /\/net-ssh/,
+        /\/net-sftp/
       ].freeze
 
       def initialize(debug: false, force_cause: [])