Update to React 18

[t3chguy]

Update to testing-library has to be done in lock-step as >=v13 only supports React 18. @testing-library/react-hooks is now within the core @testing-library/react module.

For https://github.com/vector-im/wat-internal/issues/65 Requires https://github.com/matrix-org/matrix-react-sdk/pull/12852 Requires https://github.com/vector-im/element-web/pull/24763 Requires https://github.com/matrix-org/matrix-react-sdk/pull/12859 Requires https://github.com/matrix-org/matrix-react-sdk/pull/12860

[dzienisz]

what is going on with this PR?

[t3chguy]

@dzienisz https://github.com/matrix-org/matrix-react-sdk/pull/10311#issuecomment-1466199044 has the latest