Don't cache app types in DB any more

[PVince81]

During development, it happens that someone changes the app types in info.xml but forgets to increase the version number or is simply reusing the current app code.

A lot of time was lost debugging to find out why some events were not triggered. The problem was that the types in the DB did not match the ones in info.xml.

This brings me to the question of: why are we still caching the app types in the database ?
I think nowadays we anyway need to parse info.xml. As far as I remember there is already a mechanism in place to cache info.xml in memcache and observe the mtime of the file for changes.
There is likely no need any more to cache the types in the database.

Thoughts ? @DeepDiver1975 @butonic @tomneedham @micbar

[ownclouders]

GitMate.io thinks possibly related issues are #30144 (Do not cache app path if app is not found), #30150 ([Stable10] Do not cache app path if app is not found), #3322 (File Delete in Mobile App, But Media DB is Remain and not delete), #29594 (db:convert-type: Comumn not found 'execution_duration'), and #6145 (Cache db queries to appconfig table).