fix: add alt text for README images

Author: ptsouchlos

README.md

@@ -1,13 +1,13 @@
 <h1 align="center">
-  <img src="assets/images/header.png" alt="Header">
+  <img src="assets/images/header.png" alt="Snippet of resume template">
   <br><br>
   Modern CV
 </h1>
 
 [![say thanks](https://img.shields.io/badge/Say%20Thanks-👍-1EAEDB.svg)](https://github.com/ptsouchlos/modern-cv/stargazers)
-[![Discord](https://img.shields.io/discord/652515194572111872?logo=Discord)](https://discord.gg/CX2ybByRnt)
-![Release](https://img.shields.io/github/v/release/ptsouchlos/modern-cv)
-[![Tests](https://github.com/ptsouchlos/modern-cv/actions/workflows/tests.yml/badge.svg)](https://github.com/ptsouchlos/modern-cv/actions/workflows/tests.yml)
+[![Discord logo](https://img.shields.io/discord/652515194572111872?logo=Discord)](https://discord.gg/CX2ybByRnt)
+![Latest release button](https://img.shields.io/github/v/release/ptsouchlos/modern-cv)
+[![Test CI badge](https://github.com/ptsouchlos/modern-cv/actions/workflows/tests.yml/badge.svg)](https://github.com/ptsouchlos/modern-cv/actions/workflows/tests.yml)
 
 A port of the [Awesome-CV](https://github.com/posquit0/Awesome-CV) Latex resume template in [typst](https://github.com/typst/typst).
 
@@ -22,10 +22,10 @@ A port of the [Awesome-CV](https://github.com/posquit0/Awesome-CV) Latex resume
 
 ## Preview
 
-| Resumes                                | Cover letters                                     |
-| -------------------------------------- | ------------------------------------------------- |
-| ![Resume](assets/images/resume.png)    | ![Cover Letter](assets/images/coverletter.png)    |
-| ![Resume 2](assets/images/resume2.png) | ![Cover Letter 2](assets/images/coverletter2.png) |
+| Resumes                                                | Cover letters                                                     |
+| ------------------------------------------------------ | ----------------------------------------------------------------- |
+| ![Resume template output](assets/images/resume.png)    | ![Cover Letter template output](assets/images/coverletter.png)    |
+| ![Resume 2 template output](assets/images/resume2.png) | ![Cover Letter 2 template output](assets/images/coverletter2.png) |
 
 ## Requirements