docs: Update documentation site header to A-Bash Book

Author: darkdestry-t

docs/_sass/minima/_base.scss

@@ -288,7 +288,7 @@ table {
     text-align: center;
   }
   .site-header:before {
-    content: "AB-3";
+    content: "A-Bash Book";
     font-size: 32px;
   }
 }