[playground:ci] Don't install compiler deps twice (#31995)

The compiler playground already installs the compiler's dependencies in
a preinstall step. No need to repeat it in CI.

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[//]: # (BEGIN SAPLING FOOTER)
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* __->__ #31995
* #31994

.github/workflows/compiler_playground.yml

@@ -38,11 +38,7 @@ jobs:
         with:
           path: "**/node_modules"
           key: compiler-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}
-      - name: yarn install compiler
-        run: yarn install --frozen-lockfile
-        working-directory: compiler
-      - name: yarn install playground
-        run: yarn install --frozen-lockfile
+      - run: yarn install --frozen-lockfile
       - run: npx playwright install --with-deps chromium
       - run: CI=true yarn test
       - run: ls -R test-results