Fix documentation inaccuracies in Governor (#4815)

contracts/governance/extensions/GovernorTimelockAccess.sol

@@ -35,6 +35,9 @@ import {Time} from "../../utils/types/Time.sol";
  * mitigate this attack vector, the governor is able to ignore the restrictions claimed by the `AccessManager` using
  * {setAccessManagerIgnored}. While permanent denial of service is mitigated, temporary DoS may still be technically
  * possible. All of the governor's own functions (e.g., {setBaseDelaySeconds}) ignore the `AccessManager` by default.
+ *
+ * NOTE: `AccessManager` does not support scheduling more than one operation with the same target and calldata at
+ * the same time. See {AccessManager-schedule} for a workaround.
  */
 abstract contract GovernorTimelockAccess is Governor {
     // An execution plan is produced at the moment a proposal is created, in order to fix at that point the exact

contracts/governance/extensions/GovernorTimelockCompound.sol

@@ -16,7 +16,7 @@ import {SafeCast} from "../../utils/math/SafeCast.sol";
  *
  * Using this model means the proposal will be operated by the {TimelockController} and not by the {Governor}. Thus,
  * the assets and permissions must be attached to the {TimelockController}. Any asset sent to the {Governor} will be
- * inaccessible.
+ * inaccessible from a proposal, unless executed via {Governor-relay}.
  */
 abstract contract GovernorTimelockCompound is Governor {
     ICompoundTimelock private _timelock;

contracts/governance/extensions/GovernorTimelockControl.sol

@@ -11,7 +11,7 @@ import {SafeCast} from "../../utils/math/SafeCast.sol";
 /**
  * @dev Extension of {Governor} that binds the execution process to an instance of {TimelockController}. This adds a
  * delay, enforced by the {TimelockController} to all successful proposal (in addition to the voting duration). The
- * {Governor} needs the proposer (and ideally the executor) roles for the {Governor} to work properly.
+ * {Governor} needs the proposer (and ideally the executor and canceller) roles for the {Governor} to work properly.
  *
  * Using this model means the proposal will be operated by the {TimelockController} and not by the {Governor}. Thus,
  * the assets and permissions must be attached to the {TimelockController}. Any asset sent to the {Governor} will be
@@ -21,9 +21,6 @@ import {SafeCast} from "../../utils/math/SafeCast.sol";
  * risky, as it grants them the ability to: 1) execute operations as the timelock, and thus possibly performing
  * operations or accessing funds that are expected to only be accessible through a vote, and 2) block governance
  * proposals that have been approved by the voters, effectively executing a Denial of Service attack.
- *
- * NOTE: `AccessManager` does not support scheduling more than one operation with the same target and calldata at
- * the same time. See {AccessManager-schedule} for a workaround.
  */
 abstract contract GovernorTimelockControl is Governor {
     TimelockController private _timelock;