Add list of PRs to review to Java Track

Also a brief overview

Author: illicitonion

org-cyf-theme/assets/custom-theme/04-components/pr-overview.scss

@@ -12,6 +12,7 @@
     padding: var(--theme-spacing--1);
     display: grid;
     gap: var(--theme-spacing--1);
+    max-width: 285px;
   }
 
   &__age {

org-cyf/content/tracks/java/_index.md

@@ -7,3 +7,9 @@ track_kinds = ["jobs-after-sdc"]
 menu="Java"
 weight = 1
 +++
+
+This track introduces designing and building systems using the Java programming language.
+
+It assumes you already know how to build working software in another language (such as JavaScript), including multiple components which need to talk to each other (such as a frontend and a backend). It does not assume you know object-oriented programming or static typing.
+
+For volunteers: See [PRs to review](prs-needing-review/).

org-cyf/content/tracks/java/prs-needing-review/_index.md

@@ -0,0 +1,9 @@
++++
+title = "Java PRs needing review"
+layout = "needs-review"
+GitHubRepos = [
+    "Module-Java",
+]
++++
+
+### Modules in red have lots of PRs, or any old PRs needing review.