Replace jest-puppeteer with Playwright

.github/workflows/ci.yaml

@@ -51,7 +51,8 @@ jobs:
           node-version: ${{ matrix.node }}
       - run: npm ci --loglevel verbose
       - run: npm run get-data
-      - run: npm run smoke-test:ci
+      - run: npx playwright install chromium
+      - run: npm run smoke-test
 
   lint:
     runs-on: ubuntu-latest

.gitignore

@@ -7,7 +7,6 @@ big_flu
 s3/
 /local_narratives/
 /datasets/
-**/__diff_output__
 
 ### OSX ###
 .DS_Store
@@ -17,5 +16,8 @@ node_modules/
 npm-debug.log
 *tgz
 
+### playwright ###
+.playwright/
+
 ### IDE ###
 .vscode/*

DEV_DOCS.md

@@ -53,9 +53,7 @@ From a fork: `git pull --rebase upstream master`
 We use the following libraries for all kinds of testing, so it'd help to read the docs to get familiar with their APIs and features:
 
 1. [`Jest`](https://github.com/facebook/jest)
-2. [`Puppeteer`](https://github.com/puppeteer/puppeteer/)
-3. [`Jest-Puppeteer`](https://github.com/smooth-code/jest-puppeteer)
-4. [`Jest-Image-Snapshot`](https://github.com/americanexpress/jest-image-snapshot)
+2. [`Playwright`](https://playwright.dev)
 
 When you submit a pull request to the auspice repository, certain tests will need to pass before it can be merged.
 
@@ -75,11 +73,13 @@ Run `npm run lint`. If there are issues run `npm run lint:fix`.
 
 Auspice used to have integration testing using jest + puppeteer, however this was removed in [PR 1672](https://github.com/nextstrain/auspice/pull/1672).
 Ideally this functionality will be brought back, and that PR would be a good place to start.
+If embarking on this journey, consider using Playwright since it is already used for smoke tests.
 
 #### For smoke tests
 
 1. Fetch the datasets with `npm run get-data`.
-2. Ensure you are **not** currently running the site locally, then run `npm run smoke-test:ci`.
+2. Install the testing browser with `npx playwright install chromium`.
+3. Run `npm run smoke-test`.
 
 
 #### Test Tips