releng: use org.yaml.snakeyaml from orbit in e4.20 target

This needed after upgrading to Tycho 4.0.3.

Change-Id: Id8ed2e3c7f6a2066515f817bafe99004ab91244a
Signed-off-by: Bernd Hufmann <bernd.hufmann@ericsson.com>
Reviewed-on: https://git.eclipse.org/r/c/tracecompass.incubator/org.eclipse.tracecompass.incubator/+/205555
Tested-by: Patrick Tasse <patrick.tasse@gmail.com>
Tested-by: Trace Compass Bot <tracecompass-bot@eclipse.org>
Reviewed-by: Patrick Tasse <patrick.tasse@gmail.com>

common/org.eclipse.tracecompass.incubator.target/tracecompass-incubator-e4.20.target

@@ -85,6 +85,7 @@
 <unit id="org.glassfish.jersey.ext.entityfiltering.source" version="0.0.0"/>
 <unit id="org.slf4j.api" version="0.0.0"/>
 <unit id="org.slf4j.binding.simple" version="0.0.0"/>
+<unit id="org.yaml.snakeyaml" version="0.0.0"/>
 <repository location="https://download.eclipse.org/tools/orbit/downloads/drops/R20210602031627/repository/"/>
 </location>
 <location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
@@ -239,4 +240,4 @@
 -Xmx512M</vmArgs>
 <programArgs>-consolelog</programArgs>
 </launcherArgs>
-</target>
+</target>