Removing mstumpfx from CODEOWNERS
salute:
# Legacy project ownership
-* @keitwb @jcheng-splunk @mstumpfx @asuresh4 @rmfitzpatrick @signalfx/gdi-data-collection-maintainers
+* @keitwb @jcheng-splunk @asuresh4 @rmfitzpatrick @signalfx/gdi-data-collection-maintainers
# Docs reviewers
*.md @signalfx/docs @signalfx/gdi-data-collection-approvers
