chore(deps): update dependency rollup to v2.31.0

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
rollup (source)	devDependencies	minor	2.30.0 -> 2.31.0

---

Release Notes

rollup/rollup

### [`v2.31.0`](https://togithub.com/rollup/rollup/blob/master/CHANGELOG.md#​2310) [Compare Source](https://togithub.com/rollup/rollup/compare/v2.30.0...v2.31.0) _2020-10-15_ ##### Features - When using the `output.moduleToStringTag` option, also add the tag to entries with exports and simulated external namespaces ([#​3822](https://togithub.com/rollup/rollup/issues/3822)) - Add the `__esModule` interop marker to IIFE global variables unless `output.esModule` is turned off ([#​3822](https://togithub.com/rollup/rollup/issues/3822)) ##### Pull Requests - [#​3822](https://togithub.com/rollup/rollup/pull/3822): Add module toStringTag to entries and interop namespaces ([@​lukastaegert](https://togithub.com/lukastaegert))

---

Renovate configuration

:date: Schedule: At any time (no schedule defined).

:vertical_traffic_light: Automerge: Enabled.

:recycle: Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

:no_bell: Ignore: Close this PR and you won't be reminded about this update again.

---

• [ ] If you want to rebase/retry this PR, check this box

---

This PR has been generated by WhiteSource Renovate. View repository job log here.