TimelockController (v5) documentation

[Pybast]

A few feedbacks (with my current understanding of this doc):

1. Admin is not given to the deployer by default
As per the latest version of TimelockController (v5.0.0), the admin is optional and not given by default to the deployer as described below.

docs/content/contracts/5.x/access-control.mdx

Line 106 in e3504ed

By default, the address that deployed the [`TimelockController`](/contracts/5.x/api/governance#TimelockController) gets administration privileges over the timelock. This role grants the right to assign proposers, executors, and other administrators.

2. No mention of CANCELLER_ROLE
Given the importance of this role, I think it should be detailed in this section in a similar manner as minDelay is detailed.

3. No warning on CANCELLER_ROLE DOS
If a canceller missbehaves, it could cancel all transactions including the ones trying to remove it from the CANCELLER_ROLE. This would result in DOS of the underlying system.
It seems this scenario should be clearly outlined as a warning to inform teams of the importance of securing the canceller(s).

Curious and open to feedbacks on the above