Make image width constraint adjustable

Placing a `less than equal to` constraint so that when image is not present, the nil image can provide its width for stackview beside it

Author: “Akshay

swift-sdk/Resources/IterableEmbeddedView.xib

@@ -66,7 +66,7 @@ Description text</string>
                                     <rect key="frame" x="268" y="0.0" width="100" height="100"/>
                                     <constraints>
                                         <constraint firstAttribute="height" constant="100" id="8cm-im-EKi"/>
-                                        <constraint firstAttribute="width" constant="100" id="bVg-Ev-iLm"/>
+                                        <constraint firstAttribute="width" relation="lessThanOrEqual" constant="100" id="bVg-Ev-iLm"/>
                                     </constraints>
                                 </imageView>
                             </subviews>