Fix: Correct the nightly version cut off in scaladoc (#17024)

In this commit I corrected the cut off of the nightly version by
changing :
- The width in auto for desktop version
- The max-width in `calc(12 * var(--base-spacing));` for better
responsiveness

Desktop
Before:
<img width="994" alt="Screenshot 2023-03-01 at 11 04 44"
src="https://user-images.githubusercontent.com/44496264/222109159-79249ec2-359c-4782-9dcc-88c75ca10454.png">

After:
<img width="1001" alt="Screenshot 2023-03-01 at 11 04 27"
src="https://user-images.githubusercontent.com/44496264/222109141-630a85ef-d2c2-4312-b143-d54f97c2506e.png">

Mobile
Before:
<img width="409" alt="Screenshot 2023-03-01 at 11 13 07"
src="https://user-images.githubusercontent.com/44496264/222109747-253c685e-44ea-4e5d-8330-f2576c729895.png">

After:
<img width="409" alt="Screenshot 2023-03-01 at 11 07 12"
src="https://user-images.githubusercontent.com/44496264/222108968-ae3cc503-cca2-4a65-a76d-9d7e1006e131.png">

Fixes: #16588

Author: Dedelweiss

scaladoc/resources/dotty_res/styles/theme/layout/header.css

@@ -72,7 +72,7 @@
   overflow: hidden;
   white-space: nowrap;
   text-overflow: ellipsis;
-  width: calc(9 * var(--base-spacing));
+  width: auto;
 }
 
 .single {
@@ -103,6 +103,10 @@
   #search-toggle {
     display: none;
   }
+
+  .projectVersion{
+    max-width: calc(12 * var(--base-spacing));
+  }
 }