RFR: 7952: JfrRulesReport -format xml produce incorrect results

[Virag Purnam]

While generating JFR Rules Report in xml produces incorrect result for Method Profiling, Allocated Classes and Threads Allocating.


For example, for Method Profiling XML shows:

The methods that used the most CPU are:
org.openjdk.jmc.flightrecorder.rules.jdk.latency.MethodProfilingRule$MethodPro
filingWindowResult at 53fb3dab

when it should be :
org.eclipse.jetty.server.HttpOutput.acquireBuffer() (43.4 % of samples)
10/21/2022, 12:25:52.000 PM – 12:26:22 PM


After the fix, I have compared the outputs. Now it provides a readable list. Earlier it was dumping the object directly. Please refer the below screen shot. 
<img width="925" alt="7952" src="https://user-images.githubusercontent.com/97600378/214099759-1465ae74-646b-4483-994a-af323986c627.png">

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Commit messages:
 - 7952: JfrRulesReport -format xml produce incorrect results

Changes: https://git.openjdk.org/jmc/pull/463/files
 Webrev: https://webrevs.openjdk.org/?repo=jmc&pr=463&range=00
  Issue: https://bugs.openjdk.org/browse/JMC-7952
  Stats: 30 lines in 1 file changed: 26 ins; 1 del; 3 mod
  Patch: https://git.openjdk.org/jmc/pull/463.diff
  Fetch: git fetch https://git.openjdk.org/jmc pull/463/head:pull/463

PR: https://git.openjdk.org/jmc/pull/463