``ERC*Pausable`` doesn't have a public `pause()` and `unpause()` functions

[ernestognw]

🧐 Motivation
Currently, ERC20Pausable, ERC721Pausable and ERC1155Pausable doesn't have public or external pause and unpause mechanisms.

This dates since v3.0 (some context here, here, and here), in which Pausable became abstract to allow for supporting both AccessControl and Ownable as access control mechanisms.

This might need discussion before moving forward for 5.0

[ernestognw]

Tested the repo with:

function pause() external virtual;
function unpause() external virtual;

Makes compilation only fail with ERC20PresetMinterPauser, and that's in our Roadmap for deprecations, so I'm leaving this for further discussion.

[frangio]

Note that this also applies to ERC721Pausable and ERC1155Pausable.

[dirtycajunrice]

it is more code to override the public unsafe function than it is to implement it properly calling the internal function. My vote is no change

[Amxx]

Not in 5.0. Candidate for 5.x