[20843] Add action to generate flaky test reports

[EduPonz]

Description

This PR adds a flakiness_report action to create flaky tests reports in nightly workflows.
This stems from the original work done by @elianalf in:

• [20843] Detect flaky tests Github workflow Fast-DDS#4752

TODO:

• Add Windows support
• Add macOS support

Contributor Checklist

• Commit messages follow the company guidelines.
• Changes are API compatible.
• New features have been added to the versions.md and README.md files (if applicable).

Reviewer Checklist

• The title and description correctly express the PR's purpose.
• The Contributor checklist is correctly filled.

[elianalf]

This comment is just a reminder for us: if we will have problems related to storage space of the artifacts, we may need to to create a reduced version of this .xsl file saving only the necessary information related to the test results. A possible solution is the following:

Suggested change

	<xsl:variable name="duration" select="Results/NamedMeasurement[@name='Execution Time']/Value"/>
	<xsl:variable name="duration" select="Results/NamedMeasurement[@name='Execution Time']/Value"/>
	<xsl:variable name="status" select="@Status"/>
	<xsl:variable name="output" select="Results/Measurement/Value"/>
	<xsl:variable name="className" select="translate(Path, '/.', '.')"/>
	<testcase classname="projectroot{$className}"
	name="{$testName}"
	status="{$status}"
	time="{$duration}">
	</testcase>
	</xsl:for-each>
	</testsuite>
	</testsuites>
	</xsl:template>
	</xsl:stylesheet>