[SPARK-20630][WEB UI] Fixed column visibility in Executor Tab

## What changes were proposed in this pull request?

#14617 added new columns to the executor table causing the visibility checks for the logs and threadDump columns to toggle the wrong columns since they used hard-coded column numbers.

I've updated the checks to use column names instead of numbers so future updates don't accidentally break this again.

Note: This will also need to be back ported into 2.2 since #14617 was merged there

## How was this patch tested?

Manually tested

Author: Alex Bozarth <ajbozart@us.ibm.com>

Closes #17904 from ajbozarth/spark20630.