Upgrade to newest version of Playwright (#137)

Playwright 1.38 no longer installs the browsers for you:
https://github.com/microsoft/playwright/releases/tag/v1.38.0.

Local users should rerun the below:

```
npm install
npx playwright install
```

.github/workflows/deploy-staging.yaml

@@ -14,7 +14,9 @@ jobs:
         with:
           node-version: 18
       - name: Install dependencies
-        run: npm ci
+        run: |
+          npm ci
+          npx playwright install --with-deps
       - name: Build
         run: npm run build
       - name: Run tests on dist/

.github/workflows/tests.yaml

@@ -12,7 +12,9 @@ jobs:
         with:
           node-version: 18
       - name: Install dependencies
-        run: npm ci
+        run: |
+          npm ci
+          npx playwright install --with-deps
       - name: Lint
         run: npm run lint
       - name: Run tests

README.md

@@ -15,6 +15,15 @@ You will also need to install:
 
 To run the below commands, open your terminal app. Make sure you have `git clone`d the fork of your repository somewhere on your machine. Then, use `cd <directory>` to navigate there, e.g. `cd code/parking-lot-map`.
 
+## Prereq: install
+
+You must first install the project's dependencies before running any of the below commands.
+
+```bash
+❯ npm install
+❯ npx playwright install
+```
+
 ## Start the server
 
 ```bash