Fix org invite url being html encoded (#5100)

Ever since we changed to pass the full url as a template value handlebars now html-encodes this.
This causes issues with the plain/text mails, but it also could potentially cause issues with the text/html templates.

This PR encloses the template values inside triple braces `{{{ }}}` which prevents html-encoding.
Since the URL is generated via the `url` crate the values are percent-encoded anyway.

Fixes #5097

Signed-off-by: BlackDex <black.dex@gmail.com>

src/static/templates/email/send_org_invite.hbs

@@ -3,7 +3,7 @@ Join {{{org_name}}}
 You have been invited to join the *{{org_name}}* organization.
 
 
-Click here to join: {{url}}
+Click here to join: {{{url}}}
 
 
 If you do not wish to join this organization, you can safely ignore this email.

src/static/templates/email/send_org_invite.html.hbs

@@ -9,7 +9,7 @@ Join {{{org_name}}}
    </tr>
    <tr style="margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 16px; color: #333; line-height: 25px; -webkit-font-smoothing: antialiased; -webkit-text-size-adjust: none;">
       <td class="content-block" style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 16px; color: #333; line-height: 25px; margin: 0; -webkit-font-smoothing: antialiased; padding: 0 0 10px; -webkit-text-size-adjust: none; text-align: center;" valign="top" align="center">
-         <a href="{{url}}"
+         <a href="{{{url}}}"
             clicktracking=off target="_blank" style="color: #ffffff; text-decoration: none; text-align: center; cursor: pointer; display: inline-block; border-radius: 5px; background-color: #3c8dbc; border-color: #3c8dbc; border-style: solid; border-width: 10px 20px; margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; box-sizing: border-box; font-size: 16px; line-height: 25px; -webkit-font-smoothing: antialiased; -webkit-text-size-adjust: none;">
          Join Organization Now
          </a>