Fix blue underline in badges

See: https://github.com/orgs/community/discussions/79043#discussioncomment-7990622

Author: ptrstn

README.md

@@ -3,22 +3,12 @@
 </p>
 
 <p align="center">
-  <a href="https://github.com/ptrstn/shellsmith/actions/workflows/test.yaml" style="text-decoration: none;">
-    <img src="https://github.com/ptrstn/shellsmith/actions/workflows/test.yaml/badge.svg" alt="Test">
-  </a>
-  <a href="https://codecov.io/gh/ptrstn/shellsmith" style="text-decoration: none;">
-    <img src="https://codecov.io/gh/ptrstn/shellsmith/branch/main/graph/badge.svg" alt="codecov">
-  </a>
-  <a href="https://pypi.org/project/shellsmith" style="text-decoration: none;">
-    <img src="https://img.shields.io/pypi/v/shellsmith?color=%2334D058" alt="PyPI - Version">
-  </a>
-  <a href="https://github.com/psf/black" style="text-decoration: none;">
-    <img src="https://img.shields.io/badge/code%20style-black-000000.svg" alt="Code style: black">
-  </a>
+  <a href="https://github.com/ptrstn/shellsmith/actions/workflows/test.yaml"><img src="https://github.com/ptrstn/shellsmith/actions/workflows/test.yaml/badge.svg" alt="Test"></a>
+  <a href="https://codecov.io/gh/ptrstn/shellsmith"><img src="https://codecov.io/gh/ptrstn/shellsmith/branch/main/graph/badge.svg" alt="codecov"></a>
+  <a href="https://pypi.org/project/shellsmith"><img src="https://img.shields.io/pypi/v/shellsmith?color=%2334D058" alt="PyPI - Version"></a>
+  <a href="https://github.com/psf/black"><img src="https://img.shields.io/badge/code%20style-black-000000.svg" alt="Code style: black"></a>
 </p>
 
-
-
 Shellsmith is a Python toolkit and CLI for managing Asset Administration Shells (AAS), Submodels, and related resources. 
 It is designed to interact with [Eclipse BaSyx](https://www.eclipse.org/basyx/), a middleware platform for AAS that follows the [Industry 4.0 standard](https://industrialdigitaltwin.org/en/content-hub/aasspecifications).