Make order.components value check as optional

[pasahu]

Expected Behaviour

If user has configured "order.components" in "Page Rewrite Rule" OSGI configuration. The page conversion should NOT break if one the components mentioned in this configuration doesn't exist on any required page.

Actual Behaviour

If user has configured "order.components" in "Page Rewrite Rule" OSGI configuration. The page conversion breaks if one the components mentioned in this configuration doesn't exist on any required page.

Reproduce Scenario (including but not limited to)

Configure "order.components" in "Page Rewrite Rule" OSGI configuration with some components. Run page conversion on one of the page where one the component from "order.components" doesn't exist. breaks if one the components mentioned in this configuration doesn't exist on any required page. Below error (in log section) would come up & conversion will fail.

Steps to Reproduce

Configure "order.components" in "Page Rewrite Rule" OSGI configuration with some components. Run page conversion on one of the page where one the component from "order.components" doesn't exist. breaks if one the components mentioned in this configuration doesn't exist on any required page. error shown in log section would come up & conversion will fail.

Platform and Version

Version-2.1.0

Sample Code that illustrates the problem

Logs taken while reproducing problem

07.08.2022 21:23:12.399 *ERROR* [sling-threadpool-16016acd-95ff-4744-baaf-e0fb3661542c-(apache-sling-job-thread-pool)-1-AEM Modernize Tools Queue(com/adobe/aem/modernize/job/topic/convert/structure)] com.adobe.aem.modernize.structure.job.PageStructureJobExecutor Page structure conversion resulted in an error.
com.adobe.aem.modernize.RewriteException: Repository exception while performing rewrite operation.
	at com.adobe.aem.modernize.structure.impl.StructureRewriteRuleServiceImpl.apply(StructureRewriteRuleServiceImpl.java:106) [com.adobe.aem.aem-modernize-tools.core:2.1.0]
	at com.adobe.aem.modernize.structure.job.PageStructureJobExecutor.doProcess(PageStructureJobExecutor.java:98) [com.adobe.aem.aem-modernize-tools.core:2.1.0]
	at com.adobe.aem.modernize.job.AbstractConversionJobExecutor.process(AbstractConversionJobExecutor.java:82) [com.adobe.aem.aem-modernize-tools.core:2.1.0]
	at org.apache.sling.event.impl.jobs.queues.JobQueueImpl.startJob(JobQueueImpl.java:351) [org.apache.sling.event:4.2.24]
	at org.apache.sling.event.impl.jobs.queues.JobQueueImpl.access$100(JobQueueImpl.java:60) [org.apache.sling.event:4.2.24]
	at org.apache.sling.event.impl.jobs.queues.JobQueueImpl$1.run(JobQueueImpl.java:287) [org.apache.sling.event:4.2.24]
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
	at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: javax.jcr.ItemNotFoundException: Not a child: dropdown1
	at org.apache.jackrabbit.oak.jcr.delegate.NodeDelegate.orderBefore(NodeDelegate.java:370) [org.apache.jackrabbit.oak-jcr:1.42.0.T20220505140541-fbdad6b]
	at org.apache.jackrabbit.oak.jcr.session.NodeImpl$6.performVoid(NodeImpl.java:339) [org.apache.jackrabbit.oak-jcr:1.42.0.T20220505140541-fbdad6b]
	at org.apache.jackrabbit.oak.jcr.delegate.SessionDelegate.performVoid(SessionDelegate.java:280) [org.apache.jackrabbit.oak-jcr:1.42.0.T20220505140541-fbdad6b]
	at org.apache.jackrabbit.oak.jcr.session.NodeImpl.orderBefore(NodeImpl.java:330) [org.apache.jackrabbit.oak-jcr:1.42.0.T20220505140541-fbdad6b]
	at com.adobe.aem.modernize.structure.rule.PageRewriteRule.orderNodes(PageRewriteRule.java:285) [com.adobe.aem.aem-modernize-tools.core:2.1.0]
	at com.adobe.aem.modernize.structure.rule.PageRewriteRule.applyTo(PageRewriteRule.java:175) [com.adobe.aem.aem-modernize-tools.core:2.1.0]
	at com.adobe.aem.modernize.structure.impl.StructureRewriteRuleServiceImpl.apply(StructureRewriteRuleServiceImpl.java:101) [com.adobe.aem.aem-modernize-tools.core:2.1.0]
	... 8 common frames omitted