Add missing caption (#541)

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#### Summary <!-- Provide a general summary of your changes -->
Add missing caption to Email Viewer group

#### Work Item(s) <!-- Add the issue number here after the #. The issue
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Fixes
[AB#498434](https://dynamicssmb2.visualstudio.com/1fcb79e7-ab07-432a-a3c6-6cf5a88ba4a5/_workitems/edit/498434)

src/System Application/App/Email/src/Email/Outbox/EmailEditor.Page.al

@@ -32,7 +32,7 @@ page 13 "Email Editor"
         {
             group("Email Details")
             {
-                Caption = 'Email details';
+                Caption = 'Email Details';
 
                 grid("Email Details Grid")
                 {

src/System Application/App/Email/src/Email/Sent/EmailViewer.Page.al

@@ -27,6 +27,8 @@ page 12 "Email Viewer"
         {
             group("Email Details")
             {
+                Caption = 'Email Details';
+
                 grid("Email Details Grid")
                 {
                     group("Email Inner Details")