BI-555 - Npm install falls with a NullPointerException (jfrog#433)

Author: yahavi

build-info-extractor-npm/src/main/java/org/jfrog/build/extractor/npm/extractor/NpmBuildInfoExtractor.java

@@ -332,8 +332,10 @@ static Map<String, Dependency> getDependenciesMapFromBuild(Build build) {
         List<Module> modules = build.getModules();
         for (Module module : modules) {
             List<Dependency> dependencies = module.getDependencies();
-            for (Dependency dependency : dependencies) {
-                previousBuildDependencies.put(dependency.getId(), dependency);
+            if (dependencies != null) {
+                for (Dependency dependency : dependencies) {
+                    previousBuildDependencies.put(dependency.getId(), dependency);
+                }
             }
         }
         return previousBuildDependencies;