GH issues 1428: remove reference to ZGC being experimental [v/5.3] (#…

…1434)

Backport of #1433

#1428

Co-authored-by: Rob Swain <[email protected]>

docs/modules/ROOT/pages/capacity-planning.adoc

@@ -616,9 +616,7 @@ collector. We found it to work well without any tuning parameters. Its
 current downside is that it handles less throughput compared to G1 and,
 being non-generational, doesn't work well if you have a lot of static
 data on the heap (for example, if your data pipeline has a `hashJoin`
-stage). ZGC is an experimental collector under intense development, so
-you can expect further improvements, including generational GC behavior,
-in the future.
+stage).
 
 In our tests we found that as of JDK version 14.0.2, the other
 low-latency collector, Shenandoah, still did not perform as well as ZGC