Let gatsby-source-filesystem handle filenames

[damianstasik]

I noticed that image assets generated with gatsby-source-strapi have two extensions in the filename: original and target extension.

Input: my_filename.jpg (original image is JPG)
Output: my_filename.jpg.png (when querying PNG image)

There were two solutions for this:

1. Pass extension-less filename to name
2. Let gatsby-source-filesystem handle the name and extension retrieval

I went with the second solution as gatsby-source-filesystem handles special characters (spaces, brackets, etc.) out of the box, but also adds additonal file hash to the filename for better cache invalidation.

[remidej]

Hello @visualfanatic, thanks for the PR

Input: my_filename.jpg (original image is JPG)
Output: my_filename.jpg.png (when querying PNG image)

I'm not sure what you mean when you say you're querying a JPG image as a PNG. Can you share a code snippet as an example?

[remidej]

Even without the extension change question mentioned above, I could find the issue. When you fetch an image's absolute path, there is indeed an issue with double extensions (like image.png.png).

And now that I see the problem, I can confirm that this PR fixes it. Thanks!

[damianstasik]

@remidej sorry for the confusion, it should be webp instead of jpg. Gatsby converts webp to png when preparing the image to be used in gatsby-image/gatsby-plugin-image.