Add missing null check

Author: Rawi01

src/eclipseAgent/lombok/eclipse/agent/PatchJavadoc.java

@@ -53,6 +53,7 @@ public static String getHTMLContentFromSource(String original, IJavaElement memb
 			if (iCompilationUnit instanceof CompilationUnit) {
 				CompilationUnit compilationUnit = (CompilationUnit) iCompilationUnit;
 				Map<String, String> docs = EclipseAugments.CompilationUnit_javadoc.get(compilationUnit);
+				if (docs == null) return null;
 
 				String signature = getSignature(sourceMethod);
 				String rawJavadoc = docs.get(signature);