Update to React 18

.eslintrc

__tests__/integration/mirador/invalid-api-response.test.js

__tests__/src/actions/canvas.test.js

__tests__/src/components/App.test.js

__tests__/src/components/PrimaryWindow.test.js

__tests__/src/lib/MiradorViewer.test.js

__tests__/utils/test-utils.js

package.json

src/lib/MiradorViewer.js

src/state/createStore.js

src/state/selectors/manifests.js

webpack.config.js