Update performance-guidelines.md (dotnet/coreclr#23183)
authorHan Lee <han.lee@intel.com>
Fri, 15 Mar 2019 14:43:28 +0000 (07:43 -0700)
committerStephen Toub <stoub@microsoft.com>
Fri, 15 Mar 2019 14:43:28 +0000 (10:43 -0400)
commitf30249756ec97f36a3d9288f4d29f8fa1f66ff9d
tree99ecba623a4d933dba029e732e6a09dd6f9a634d
parente655e740d10b60bc0c0d6fe1cf95ccbbead71ba1
Update performance-guidelines.md (dotnet/coreclr#23183)

so that it uses run-xunit-perf.py command. run-xunit-perf.cmd is no longer there.

Commit migrated from https://github.com/dotnet/coreclr/commit/335df1f075f06653b01838c9e64e6ee31d5f60cf
docs/coreclr/project-docs/performance-guidelines.md