[FIX] theme_kea: add missing images

Commit [1] introduced new images for the theme, alongside their related
ir.attachment definition. Later, a refactoring of the theme was made at
commit [2]. During that refactoring, multiple mistakes were made. Three
image files were removed: s_image_text.jpg, s_text_image.jpg and
s_banner.jpg. Out of these 3, only one related ir.attachment was
adapted to not use the removed image anymore: s_banner. Thus this left
two dead ir.attachment pointing to images that do not exist anymore.
Note that the banner image was actually restored later at [3]. Until
there... just dead code, although it could potentially be used and crash
by custo (this is why this targets the same version as [2]). Indeed, [2]
also patched the use of those two removed images in their related
snippet by changing the related image sources directly (using a special
route of the web_editor which generates SVG).

However, in [4], we started using one of those two images (via its xmlid
/ key) in another snippet: the new image snippet. This thus break the
kea theme when using that new snippet because the ir.attachment that is
used for that image still referenced an image that was removed by [2].

[1]: odoo/design-themes-old@66bf0fc
[2]: 004e383
[3]: 5b8e14b
[4]: odoo/odoo@507b80a

opw-3689096

closes #777

X-original-commit: 5778e69
Signed-off-by: Quentin Smetz (qsm) <[email protected]>

Author: qsm-odoo