Alt text is not descriptive [../functions file]

[timngyn]

Describe the content issue:
Images listed below do not have descriptive/informative alt text. For markdown the alt text is located between the square brackets, ![alt text](...).

The list below isn't exhaustive since I found these images based on the word count for the alt text, but it should be a good starting point to make our alt text better for people who use screen readers.

Some resources to help write alt text:

• https://webaim.org/techniques/alttext/
• https://www.a11yproject.com/posts/are-you-making-these-five-mistakes-when-writing-alt-text/

 
https://github.com/aws-amplify/docs/blob/main/src/pages/[platform]/build-a-backend/functions/layers/index.mdx:

  55  
  56: ![Lambda layer architecture diagram](/images/layers-architecture.gif)
  57