PDF Exports of wiki page with centered images don't include images.

Steps to reproduce:

1. Create a page and insert an image jpg, png etc...
2. Export the page to PDF. You should see that the image(s) did export.
3. Edit the page and align the image to the center.
4. Export the page to PDF again.
   Expected result: Image shows in the center.
   Actual result: Image is not displayed.

Cause:
The alignment done using the image tags is not being exported:

This is the "Storage Format" of a centered image that is not exported to PDF:

<p><ac:image ac:align="center"><ri:attachment ri:filename="image.jpg"><ri:page ri:content-title="Images Page" ri:space-key="KB" /></ri:attachment></ac:image></p>

and this is the one of an image centered by using the workaround and is exported to PDF (without alignment)

<p style="text-align: center;"><ac:image><ri:attachment ri:filename="image.jpg"><ri:page ri:content-title="Images Page" ri:space-key="KB" /></ri:attachment></ac:image></p>

Workaround:
center-align the cursor before including the image to the page.
The image will be added in the center and will be displayed in PDF exports.