style: Suppress Performance/StringIdentifierArgument cop

```
Performance/StringIdentifierArgument: Use :"after_#{action}" instead of "after_#{action}".
```

lib/god/cli/command.rb

@@ -27,7 +27,7 @@ def setup
       def dispatch
         if %w[load status signal log quit terminate].include?(@command)
           setup
-          send("#{@command}_command")
+          send(:"#{@command}_command")
         elsif %w[start stop restart monitor unmonitor remove].include?(@command)
           setup
           lifecycle_command

lib/god/contact.rb

@@ -28,7 +28,7 @@ def self.defaults
     end
 
     def arg(name)
-      instance_variable_get("@#{name}") || self.class.instance_variable_get("@#{name}")
+      instance_variable_get(:"@#{name}") || self.class.instance_variable_get(:"@#{name}")
     end
 
     # Normalize the given notify specification into canonical form.

lib/god/watch.rb

@@ -284,7 +284,7 @@ def call_action(condition, action)
       before_items = behaviors
       before_items += [condition] if condition
       before_items.each do |b|
-        info = b.send("before_#{action}")
+        info = b.send(:"before_#{action}")
         if info
           msg = "#{name} before_#{action}: #{info} (#{b.base_name})"
           applog(self, :info, msg)
@@ -304,7 +304,7 @@ def call_action(condition, action)
       after_items = behaviors
       after_items += [condition] if condition
       after_items.each do |b|
-        info = b.send("after_#{action}")
+        info = b.send(:"after_#{action}")
         if info
           msg = "#{name} after_#{action}: #{info} (#{b.base_name})"
           applog(self, :info, msg)

test/test_process.rb

@@ -136,7 +136,7 @@ def test_call_action_should_write_pid
       @p.expects(:fork)
       Process.expects(:waitpid)
       File.expects(:write).with(@p.default_pid_file, pid)
-      @p.send("#{action}=", 'run')
+      @p.send(:"#{action}=", 'run')
       @p.call_action(action)
     end
   end
@@ -260,7 +260,7 @@ def test_call_action_with_invalid_command_class_should_raise
   def test_start_stop_restart_bang
     [:start, :stop, :restart].each do |x|
       @p.expects(:call_action).with(x)
-      @p.send("#{x}!")
+      @p.send(:"#{x}!")
     end
   end
 end