Fix cannot find warning icon caused NPE issue

Author: t-rufang

PluginsAndFeatures/azure-toolkit-for-intellij/src/com/microsoft/azuretools/ijidea/ui/BypassCertificateVerificationWarningForm.java

@@ -45,7 +45,7 @@ protected BypassCertificateVerificationWarningForm(@Nullable Project project) {
     }
 
     protected void createUIComponents() {
-        warningIconLabel = new JLabel(UIUtil.getBalloonWarningIcon());
+        warningIconLabel = new JLabel(UIUtil.getWarningIcon());
     }
 
     @Nullable

PluginsAndFeatures/azure-toolkit-for-intellij/src/com/microsoft/azuretools/ijidea/ui/WarningMessageForm.form

@@ -3,7 +3,7 @@
   <grid id="27dc6" binding="contentPanel" layout-manager="GridLayoutManager" row-count="2" column-count="2" same-size-horizontally="false" same-size-vertically="false" hgap="-1" vgap="-1">
     <margin top="0" left="0" bottom="0" right="0"/>
     <constraints>
-      <xy x="20" y="20" width="704" height="400"/>
+      <xy x="20" y="20" width="740" height="400"/>
     </constraints>
     <properties/>
     <border type="none"/>
@@ -15,10 +15,9 @@
         <properties/>
         <border type="none"/>
         <children>
-          <component id="5346e" class="javax.swing.JLabel" binding="warningIconLabel">
+          <component id="5346e" class="javax.swing.JLabel" binding="warningIconLabel" custom-create="true">
             <constraints border-constraint="North"/>
             <properties>
-              <icon value="javax/swing/plaf/metal/icons/ocean/warning.png"/>
               <text value=""/>
             </properties>
           </component>

PluginsAndFeatures/azure-toolkit-for-intellij/src/com/microsoft/azuretools/ijidea/ui/WarningMessageForm.java

@@ -24,6 +24,7 @@
 
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.ui.DialogWrapper;
+import com.intellij.util.ui.UIUtil;
 import com.microsoft.azuretools.azurecommons.helpers.NotNull;
 import com.microsoft.azuretools.azurecommons.helpers.Nullable;
 
@@ -56,6 +57,10 @@ public WarningMessageForm(
         }
     }
 
+    protected void createUIComponents() {
+        warningIconLabel = new JLabel(UIUtil.getWarningIcon());
+    }
+
     @Nullable
     @Override
     protected JComponent createCenterPanel() {