Improve HTML formatting

Author: marcphilipp

README.md

@@ -1,8 +1,10 @@
-<h1><picture width="200">
-  <source media="(prefers-color-scheme: dark)" srcset="https://junit.org/assets/img/junit-logo-inverted.svg">
-  <source media="(prefers-color-scheme: light)" srcset="https://junit.org/assets/img/junit-logo.svg">
-  <img alt="JUnit" src="https://junit.org/assets/img/junit-logo.svg" width="200">
-</picture></h1>
+<h1>
+  <picture width="200">
+    <source media="(prefers-color-scheme: dark)" srcset="https://junit.org/assets/img/junit-logo-inverted.svg">
+    <source media="(prefers-color-scheme: light)" srcset="https://junit.org/assets/img/junit-logo.svg">
+    <img alt="JUnit" src="https://junit.org/assets/img/junit-logo.svg" width="200">
+  </picture>
+</h1>
 
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