integration test for extra warResources

[jtnord]

IT in preparation for updating filtering code.

• Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• Ensure that the pull request title represents the desired changelog entry
• Please describe what you did
• Link to relevant issues in GitHub or Jira
• Link to relevant pull requests, esp. upstream and downstream changes
• Ensure you have provided tests - that demonstrates feature works or fixes the issue

[jtnord]

2 properties in the pom for filtering

[jtnord]

we had no test coverage of this.

There appears to be only a few plugins webResources and fewer using filtering, but there could be closed source ones and this is publicly documented so leaving the functionallity for now.

[jtnord]

maven-hpi-plugin/src/main/java/org/jenkinsci/maven/plugins/hpi/AbstractHpiMojo.java

Lines 382 to 401 in b105426

	private Properties getBuildFilterProperties()
	throws MojoExecutionException {
	// System properties
	Properties filterProperties = new Properties(System.getProperties());
	// Project properties
	filterProperties.putAll(project.getProperties());
	for (String filter : filters) {
	try {
	Properties properties = PropertyUtils.loadProperties(new File(filter));
	filterProperties.putAll(properties);
	}
	catch (IOException e) {
	throw new MojoExecutionException("Error loading property file '" + filter + "'", e);
	}
	}
	return filterProperties;
	}

[jtnord]

possibly not the best system property to use...
java.vendor.url could be better and checking the replacement starts with https://

but as this currently does not work there is not much point in changing...