Update status only if material has changed

[alirezamirian]

It's common to have many repositories that follow the same structure, in a way that you could have a single general pipeline with multiple materials and figure out which one to build based on GO_MATERIAL_[MATERIAL_NAME]_HAS_CHANGED env variables.
Right now, if we do so, all pull requests in different materials will be updated no matter if they triggered the pipeline or not. It would be nice if a check is added here:

gocd-build-status-notifier/common/src/main/java/com/tw/go/plugin/BuildStatusNotifierPlugin.java

Lines 155 to 176 in d1bafa7

	for (Map materialRevision : materialRevisions) {
	Map material = (Map) materialRevision.get("material");
	if (isMaterialOfType(material, provider.pollerPluginId())) {
	Map materialConfiguration = (Map) material.get("scm-configuration");
	String url = (String) materialConfiguration.get("url");
	List<Map> modifications = (List<Map>) materialRevision.get("modifications");
	String revision = (String) modifications.get(0).get("revision");
	Map modificationData = (Map) modifications.get(0).get("data");
	String prId = (String) modificationData.get("PR_ID");
	if (StringUtils.isEmpty(prId)) {
	prId = (String) modificationData.get("CURRENT_BRANCH");
	}
	try {
	provider.updateStatus(url, pluginSettings, prId, revision, pipelineStage, result, trackbackURL);
	} catch (Exception e) {
	LOGGER.error(String.format("Error occurred. Could not update build status - URL: %s Revision: %s Build: %s Result: %s", url, revision, pipelineInstance, result), e);
	}
	}
	}

to run updateStatus only if that material has changed. It makes sense to me to have that check unconditionally, but at least it can be a configuration if I'm missing something.