Prevent CoverityLauncherDecorator from infinitely recursing.

When a JDK (or presumably another 'tool') is automatically installed by Jenkins,
decorators are added to the launcher used to run the install script. Since
CoverityLauncherDecorator calls build.getEnvironment(), which installs these JDKs,
the call recurses infinitely, hanging the build.

The implemented solution automatically ignores decorating these scripts by looking
at the script name and path.