Update CONTRIBUTING.md
When I do the test, I found the change (line 119) "from Gaudi.Configuration import appendPostConfigAction" is needed, otherwise the line 151 "appendPostConfigAction( doIt )" will cause bug report.
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When I do the test, I found the change (line 119) "from Gaudi.Configuration import appendPostConfigAction" is needed, otherwise the line 151 "appendPostConfigAction( doIt )" will cause bug report.