Bugfix: Fix memory leak

[adamdempsey90]

PR Summary

Testing in a downstream code caught a bad memory leak related to the tasks that would eventually crash the node. I tracked this down to the use of abi::__cxa_demangle for the task graph output machinery. abi::__cxa_demangle for one reason or another explicitly calls malloc for the name it returns. So we have to call free on the name after it's used.

I can confirm that this change fixes the memory leak.

PR Checklist

• Code passes cpplint
• New features are documented.
• Adds a test for any bugs fixed. Adds tests for new features.
• Code is formatted
• Changes are summarized in CHANGELOG.md
• Change is breaking (API, behavior, ...)
  • Change is additionally added to CHANGELOG.md in the breaking section
  • PR is marked as breaking
  • Short summary API changes at the top of the PR (plus optionally with an automated update/fix script)
• CI has been triggered on Darwin for performance regression tests.
• Docs build
• (@lanl.gov employees) Update copyright on changed files

[pdmullen]

Holy cow I cannot believe you were able to track this down...

[Yurlungur]

Wow nice catch!