Extension lists contain stale data during updates.

Problem/Motivation

If access extension list information during an update, we get stale information about extensions, that are being updated.
An example of this would be an implementation of hook_requirements, that checks for the minimum version of a module A. If module A was updated, we would get the previous version of that module, since ExtensionList::getAllAvailableInfo() returns cached data. What we actually would like to get is the new version of module A.
Due to reasons described in #2863986: Allow updating modules with new service dependencies it is not always possible, or desirable, to rebuild caches before running updates.

Proposed resolution

A possible solution would be to clear extension list caches for updates.

Remaining tasks

• agree upon a solution
• implement

User interface changes

none.

API changes

none.

Data model changes

none.

Release notes snippet

none.