Describe the bug
When sending a newsletter with a long button text, it will not display correctly on Outlook devices. Some text can be cut from the button and therefore barely readable.

It may seem like a non-issue to many but the real issue here is that many people use Outlook, whether we want it or not.

To Reproduce
Steps to reproduce the behavior:

1. Go to admin panel to send a newsletter
2. Send a new newsletter with a button, apply a long button text
3. Send the newsletter to an email box using Outlook
4. See the problematic rendering

Expected behavior
I would expect the button to display correctly in Outlook.

Screenshots
Here is a screenshot of the original case:

I suspect this has something to do with the 0-borders as this is a test I did at testi.at service with the button border color swapped to black:

It appears Outlook renders the border on all lines of the hyperlinks.

Stacktrace
There's no stacktrace, this is a visual bug.

Extra data (please complete the following information):

• Device: Desktop
• Device OS: Windows 10
• Email client: Outlook (applies to all Outlook version 2007+, apparently their rendering engine is very similar)
• Decidim Version: 0.23
• Decidim installation: OmaStadi

Additional context
I believe this could be fixed by getting rid of the 0-borders. The problem is that this method is apparently the only way to apply padding in the button in Outlook based on some research about Outlook rendering.

Here's a related conversation at the foundation-email repository:
foundation/foundation-emails#416

Here is how to implement bulletproof email buttons (linked in that issue):
https://buttons.cm/

Here is some information about Outlook's HTML rendering:
https://www.avantiproducts.com/manual/wp_outlook.pdf

Alternative methods to the current 0-width border would be:

• Just getting rid of the 0-width borders and "hoping for the best". This will cause the button padding to disappear from Outlook but maybe it would help displaying the text properly (?).
• Providing a VML based alternative only displayed in Outlook as shown in the bulletproof buttons resource (closest to what you want to display)
• Applying a higher line height in the button (would break multiline buttons in other rendering engines too)
• Some resources report that adding a p-element inside the link element might help but I tried this at testi.at and could not get rid of the extra top padding in the button what this solution caused
• Adding transparent images on both sides of the button will help rendering padding according to some internet resources but this is probably very annoying to manage technically