When an action module is whitelisted, incrementMaxActionModuleIdUsed() is called, which increments _maxActionModuleIdUsed and checks that it does not exceed MAX_ACTION_MODULE_ID_SUPPORTED:
StorageLib.sol#L165-L175
MAX_ACTION_MODULE_ID_SUPPORTED is currently declared as 255:
StorageLib.sol#L47
This becomes an issue as _maxActionModuleIdUsed does not changed when action modules are un-whitelisted, which means that action module IDs cannot be reused:
GovernanceLib.sol#L105-L107
This means that only 255 action modules can ever be whitelisted, and governance will not be able to whitelist action modules forever after this limit is exceeded.
