Your problem is not that SVG images are getting indexed. The items in your screenshot are image directories. If you visit those URLs you will likely see a list of files that are in the directories. Since they are image directories, the generated index page uses the word "svg".
This is a feature of web servers called "directory index". If you have .htaccess you can turn that off:
Otherwise, you can upload an index.html file into each of those directories. The index.html file will take the place of the automatically generated directory listing. You could make the index.html file meta refresh to the home page, and put a
noindex directive in it for good measure:
<meta http-equiv="refresh" content="0; url=/">
<meta name="robots" content="noindex">
I also want to point out that svg as a content keyword is not a problem that has to be fixed. Google shows the content keywords report so that you can check for spam. If you saw "viagra" or "escorts" on that list you would know your site has been hacked with unsavory content injected onto it.
As long as the keywords in the content keyword report are not spammy, you don't have to take any action because of it.