Update multiverse run message

The message that read something like
"Running "/Users/jbunch/git/public/newrelic-ruby-
agent/test/multiverse/suites/grpc" in 2 environments in serial"
was slightly misleading, as the 2 environments would be from
a single Envfile-produced Gemfile for both chain and prepend
instrumentation permutations. It would also get repeated
when the next instrumentation permutation would start its test
run.

Now, the message reads something like:
Running "logger" suite in 1 CHAIN environment and
1 PREPEND environment in serial

And will only be printed at the top of the suite's run.

test/multiverse/lib/multiverse/runner.rb

@@ -48,6 +48,7 @@ def parse_args(args)
 
     def run(filter = "", opts = {})
       execute_suites(filter, opts) do |suite|
+        puts yellow(suite.execution_message)
         suite.each_instrumentation_method do |method|
           suite.execute(method)
         end

test/multiverse/lib/multiverse/suite.rb

@@ -422,10 +422,6 @@ def execute(instrumentation_method)
       return unless check_environment_condition
       configure_instrumentation_method(instrumentation_method)
 
-      label = should_serialize? ? 'serial' : 'parallel'
-      env_count = filter_env ? 1 : environments.size
-      puts yellow("\nRunning #{directory.inspect} in #{env_count} environments in #{label}")
-
       environments.before.call if environments.before
       if should_serialize?
         execute_serial(instrumentation_method)
@@ -681,6 +677,16 @@ def verbose?
     def exclude?(file)
       EXCLUDED_FILES.include?(File.basename(file))
     end
+
+    def execution_message
+      label = should_serialize? ? 'serial' : 'parallel'
+      env_count = filter_env ? 1 : environments.size
+      env_plural = env_count > 1 ? 'environments' : 'environment'
+      opening = "\nRunning \"#{suite}\" suite in"
+      body = environments.instrumentation_permutations.map { |p| "#{env_count} #{p.upcase} #{env_plural}" }
+      ending = "in #{label}"
+      message = [opening, body.join(' and '), ending].join(' ')
+    end
   end
 end