[FIX] mail: display correctly button on windows Outlook mail client

Steps to reproduce:

  - Install 'Sales' module (for test purpose)
  - Configure the outgoing mail server
  - Change Demo user email to an Outlook account
  - Create or Open a quotation
  - In the chatter, send a log note with `@Marc Demo`
  - Check the email received in the windows Outlook mail client

Issue:

  The button is not well displayed (the padding between the text and
  the border is not filled with the background color).

Solution:

  Use a `table` around the button(s) and move some CSS to the `td`
  around the button to display it correctly.

  [More info here](https://medium.com/email-design/outlook-rendering-issues-5-tips-to-ensure-your-emails-display-properly-9520b2456166

)

opw-3142132

closes odoo/odoo#115012

Signed-off-by: Nasreddin Boulif (bon) <bon@odoo.com>

addons/mail/data/mail_data.xml

@@ -59,19 +59,22 @@
     <table cellspacing="0" cellpadding="0" border="0" style="width: 600px; margin-top: 5px;">
     <tbody><tr>
     <td valign="center">
-        <a t-if="has_button_access"
-                t-att-href="button_access['url']"
-                style="padding: 8px 12px; font-size: 12px; color: #FFFFFF; text-decoration: none !important; font-weight: 400; background-color: #875A7B; border: 0px solid #875A7B; border-radius:3px">
-            <t t-esc="button_access['title']"/>
-        </a>
-        <t t-if="actions">
-            <t t-foreach="actions" t-as="action">
-                |
-                <a t-att-href="action['url']" style="color: #875A7B; text-decoration:none !important;">
-                    <t t-esc="action['title']"/>
+        <table cellspacing="0" cellpadding="0" border="0"><tr>
+            <td t-if="has_button_access" style="padding: 8px 12px; border-radius: 3px; background-color: #875A7B;">
+                <a t-att-href="button_access['url']" class="button-a button-a-primary"
+                    style="font-size: 12px; color: #FFFFFF; text-decoration: none !important; font-weight: 400;">
+                    <t t-esc="button_access['title']"/>
                 </a>
-            </t>
-        </t>
+            </td>
+            <td t-if="actions">
+                <t t-foreach="actions" t-as="action">
+                    |
+                    <a t-att-href="action['url']" style="color: #875A7B; text-decoration:none !important;">
+                        <t t-esc="action['title']"/>
+                    </a>
+                </t>
+            </td>
+        </tr></table>
     </td>
     <td valign="center" align="right">
         <img t-att-src="'/logo.png?company=%s' % (company.id or 0)" style="padding: 0px; margin: 0px; height: auto; max-width: 200px; max-height: 36px;" t-att-alt="'%s' % company.name"/>