Update enzyme in /modules/frontend from 3.3.0 to 3.7.0

[dependencies]

Dependencies.io has updated enzyme (a npm dependency in /modules/frontend) from "3.3.0" to "3.7.0".

3.7.0

New Stuff

• mount: .state()/.setState(): allow calling on children (#1802, ljharb)
• configuration: add reset (commit)

Fixes

• makeOptions: ensure that config-level attachTo/hydrateIn are inherited into wrapper options (#1836, ljharb)
• shallow/Utils: call into adapter’s isCustomComponentElement if present (#1832, SinHouse)
• shallow/mount: throw an explicit error when state is null/undefined (commit)
• freeze ROOT_NODES for child wrappers (#1811, jgzuke)
• shallow: .parents: ensure that one .find call does not affect another (#1781, ljharb)
• mount: update after simulateError (#1812, jgzuke)

Refactors

• mount/shallow: getElement: use this.single (commit)