Changed excessively long alt text for 2 images (#885)

* Changed alt text for 2 images.

* Changed excessively long alt text

* Update alt text to be more descriptive

* Update alt text on setting-up-your-environment.mdx

---------

Co-authored-by: kit <1304340+ksen0@users.noreply.github.com>

Author: sprinklehappiness

src/content/tutorials/en/setting-up-your-environment.mdx

@@ -4,7 +4,7 @@ description: A quick tutorial for setting up the p5.js Web Editor and VS Code to
 category: introduction
 categoryIndex: 0
 featuredImage: ../images/featured/SetupA.jpg
-featuredImageAlt: An interactive sketch in the p5.js Web Editor draws circles on the canvas as the mouse pointer moves.
+featuredImageAlt: An interactive sketch in the p5.js Editor draws circles on the canvas as the mouse pointer moves.
 relatedContent:
   references:
     - en/p5/setup
@@ -73,7 +73,8 @@ If you are new to p5.js, start with the [p5.js Web Editor](https://editor.p5js.o
   - Create and confirm a password. 
   - Click the “Sign Up” button.
 
-![A user clicks the “Sign Up” button in the p5.js Web Editor,  enters a new username, email address, and password.](../images/introduction/editor-signup.gif)
+
+![An arrow pointing to the highlighted fields on the Sign Up page, as described above.](../images/introduction/p5_editor_sign_up_page.png)
 
 - Using a Google account
   - Click on the button on the bottom of the page that says “Login with Google.”