[platform] add readme for dianostics util module
[platform] add readme for dianostics util module

GitOrigin-RevId: 6651fb1fe679ed01b1606a1746f5aab8c57264d8
allotria/intellij-community,allotria/intellij-community,allotria/intellij-community,allotria/intellij-community,allotria/intellij-community,allotria/intellij-community,allotria/intellij-community,allotria/intellij-community,allotria/intellij-community,allotria/intellij-community,allotria/intellij-community,allotria/intellij-community,allotria/intellij-community