Fix test pdfs with 0 height or width rectangles

DEVSIX-4538

Author: e-zhavoronok

src/test/java/com/itextpdf/html2pdf/css/w3c/css_backgrounds/BackgroundClip007Test.java

@@ -24,7 +24,6 @@ This file is part of the iText (R) project.
 
 import com.itextpdf.html2pdf.css.w3c.W3CCssTest;
 
-// TODO DEVSIX-4538 consider whether it is possible not to draw a rectangle when width or height equals to zero
 public class BackgroundClip007Test extends W3CCssTest {
     @Override
     protected String getHtmlFileName() {

src/test/java/com/itextpdf/html2pdf/css/w3c/css_backgrounds/BackgroundClip008Test.java

@@ -24,7 +24,6 @@ This file is part of the iText (R) project.
 
 import com.itextpdf.html2pdf.css.w3c.W3CCssTest;
 
-// TODO DEVSIX-4538 consider whether it is possible not to draw a rectangle when width or height equals to zero
 public class BackgroundClip008Test extends W3CCssTest {
     @Override
     protected String getHtmlFileName() {

src/test/java/com/itextpdf/html2pdf/css/w3c/css_backgrounds/BackgroundClip010Test.java

@@ -24,7 +24,6 @@ This file is part of the iText (R) project.
 
 import com.itextpdf.html2pdf.css.w3c.W3CCssTest;
 
-// TODO DEVSIX-4538 consider whether it is possible not to draw a rectangle when width or height equals to zero
 public class BackgroundClip010Test extends W3CCssTest {
     @Override
     protected String getHtmlFileName() {