…ew schema. (#14183)

fix-up of #14132

Summary of the issue:
When upgrading configurations to the new versions of the schema we often need to check what value was set previously as not to change user preferences. In our profile upgrade steps we relied on the fact that false values in the config are falthy in the boolean context, but at the state where profile is upgraded these are not yet transformed into right types, so a value set to False is set to literal string "False" which is always truthy in a boolean context.
I've discovered this when, after #14132 got merged, in the profile where I had reporting of row and column headers disabled it got re-enabled after the schema update.

Description of user facing changes
People who have reporting of row and column header disabled would still have them disabled after updating to NVDA 2022.4.

Description of development approach
In places where we check if the option is set to True in our profile upgrade steps I used the default configobj converter between string and booleans to convert options into the right values. In addition I've removed some unnecessary pass statements and some variables capturing exceptions which weren't used.
While fixing previous upgrade steps would not help people who are upgrading NVDA regularly it still made sense to do so, to support people who skipped several upgrades and to have consistent style for the upgrade steps.