[Tables] Address performance issues observed in testathon (#2112)

* Use datum key of 'utc' for timestamp

* Do not try to get column values for data that does not have those values

* Collapse current time system columns

* Noop parsing for numbers in LocalTimeFormat

* Do not attempt to provide data for columns that object does not have telemetry for. Fixes #2027

platform/features/table/res/templates/telemetry-table.html

@@ -3,7 +3,7 @@
     <mct-table
         headers="headers"
         rows="rows"
-        time-columns="tableController.timeColumns"
+        time-columns="[tableController.table.timeSystemColumnTitle]"
         format-cell="formatCell"
         enableFilter="true"
         enableSort="true"