Bump newrelic_rpm from 3.9.0.229 to 6.2.0.354

Bumps [newrelic_rpm](https://github.com/newrelic/rpm) from 3.9.0.229 to 6.2.0.354.
- [Release notes](https://github.com/newrelic/rpm/releases)
- [Changelog](https://github.com/newrelic/rpm/blob/master/CHANGELOG.md)
- [Commits](newrelic/newrelic-ruby-agent@3.9.0.229...6.2.0.354)

Signed-off-by: dependabot[bot] <support@dependabot.com>

Author: dependabot-support

Gemfile.lock

@@ -738,7 +738,7 @@ GEM
     neat (1.5.1)
       bourbon (>= 3.1)
       sass (~> 3.2.19)
-    newrelic_rpm (3.9.0.229)
+    newrelic_rpm (6.2.0.354)
     nokogiri (1.10.1)
       mini_portile2 (~> 2.4.0)
     normalize-rails (4.1.1)