Introduce reportTestTimestamp option and include timestamp for test sets and test cases

[kevinnammour]

New feature, improvement proposal

Summary

Introduce an explicit test timestamp field in XML reports at both the testsuite and testcase levels. This enhancement will allow each test suite and individual test case to record the precise processing time of execution.

The addition of test timestamps makes it easier to correlate test execution events with external, time-based system metrics such as CPU usage, memory consumption, I/O activity, JVM metrics, and other system-level monitoring data.

The timestamp:

• Represent the exact processing time of execution for each test suite and test case
• Use ISO‑8601 format (UTC) for interoperability
• Only shown when reportTestTimestamp is set to true

Motivation & Use Cases
This makes it easier to correlate test execution with time-based external signals, such as:

• CPU usage
• memory consumption
• I/O pressure
• JVM metrics
• system-level monitoring data

Report Example

<testsuite
    name="com.example.MyTest"
    timestamp="2026-01-29T06:41:12.345Z"
    time="12.345">
<testcase
    name="shouldProcessData"
    classname="com.example.MyTest"
    timestamp="2026-01-29T06:41:15.123Z"
    time="0.456">
.......

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[kevinnammour]

Hi @olamy, this is the PR we discussed a couple of weeks ago about the test timestamp reporting, please take a look when ur free.