[SPARK-3827] Very long RDD names are not rendered properly in web UI

With Spark SQL we generate very long RDD names. These names are not properly rendered in the web UI.

This PR fixes the rendering issue.

[SPARK-3827] #comment Linking PR with JIRA

Author: Hossein <hossein@databricks.com>

Closes #2687 from falaki/sparkTableUI and squashes the following commits:

fd06409 [Hossein] Limit width of cell when RDD name is too long

(cherry picked from commit d65fd554)
Signed-off-by: Josh Rosen <joshrosen@apache.org>

core/src/main/resources/org/apache/spark/ui/static/webui.css

@@ -51,6 +51,11 @@ table.sortable thead {
   cursor: pointer;
 }
 
+table.sortable td {
+  word-wrap: break-word;
+  max-width: 600px;
+}
+
 .progress {
   margin-bottom: 0px; position: relative
 }