Allow disabling of auto-creation of translation plugins

Actually, we should just be skipping the auto-creation if the $is_syncing argument is TRUE because that will avoid doing this on config sync operations, which is the issue I had.

The current hook tmgmt_modules_installed implementation is fundamentally flawed: there is no way to actually set the "auto create" to false as the annotation does not support spaces in the key as I discovered in 📌 Opt out deprecated Translator plugins from auto create Active

tmgmt_modules_installed was added as part of the initial 8.x port. I suggest this hook is removed in favor of config/install files as is customary nowadays