docs(contributors): add ADR 018 (#3922)

Co-authored-by: Josh Black <joshblack@users.noreply.github.com>

contributor-docs/adrs/adr-009-interaction-tests.md

@@ -1,5 +1,8 @@
 # ADR 009: Use Interaction testing in storybook to maintain components
 
+> **Warning**
+> This ADR is superceded by [`ADR 018`](./adr-018-interaction-tests-revisited.md)
+
 ## Status
 
 | Stage    | Status |

contributor-docs/adrs/adr-018-interaction-tests-revisited.md

@@ -0,0 +1,36 @@
+# ADR 018: Interaction testing (revisited)
+
+## Status
+
+| Stage    | Status |
+| -------- | ------ |
+| Approved | 🚧     |
+| Adopted  | 🚧     |
+
+## Context
+
+> **Note**
+> This ADR supercedes [`ADR 009`](./adr-009-interaction-tests.md)
+
+We author tests using a combination of Jest and Playwright. Typically, Jest is
+used for unit and integration tests and Playwright is used for Visual Regression
+Tests against our Storybook.
+
+In `ADR 009`, we proposed using Storybook's [`play`
+functions](https://storybook.js.org/docs/react/writing-stories/play-function) as
+the recommended way to author tests that require tests based on user
+interactions. In this ADR, we would like to revisit this decision.
+
+## Decision
+
+For tests involving interaction, use Playwright to visit a storybook story and
+interact with the component directly. This will allow for easy integration with
+Visual Regression Testing and our automated accessibility testing (through axe).
+In order to perform interactions, use [actions from
+Playwright](https://playwright.dev/docs/input).
+
+### Impact
+
+The impact of this decision is minimal as we only have one example of
+interaction stories, `UnderlineNav.interactions.stories.tsx`, and it has
+corresponding tests in Playwright.