Link to plugin's web site is reported as not found by maven linkcheck plugin.

Hello!

We use maven linkcheck plugin to check links on checkstyle's website: http://checkstyle.sourceforge.net/ . The plugin reports that on page http://checkstyle.sourceforge.net/plugins.html the following link is not found (404):
http://www.antlr.org/antlr4-maven-plugin

Links on plugins.html are generated by Apache Maven Project Info Reports Plugin. All URLs are grabbed from effective POMs of plugins.

Here is the code:

https://github.com/apache/maven-plugins/blob/trunk/maven-project-info-reports-plugin/src/main/java/org/apache/maven/report/projectinfo/PluginsReport.java#L239

https://github.com/apache/maven-plugins/blob/trunk/maven-project-info-reports-plugin/src/main/java/org/apache/maven/report/projectinfo/PluginsReport.java#L269

In effective POM.xml of maven antlr4 plugin the problematic link is:
http://www.antlr.org/antlr4-maven-plugin

As a result, we do not have an ability to change plugins urls on that page, because those links are specified by plugins developers.

So, please correct the link, because there are contradictions between linkcheck and maven antlr4 plugin.

Thank in advance!

Start by inspecting the effective POM for the ANTLR4 Maven plugin and the plugin URL consumed by the Maven Project Info Reports Plugin at PluginsReport.java lines 239 and 269. Update the incorrect URL, then verify that the generated plugins.html link no longer returns 404.

Written by the indexing model from the issue text.