ci: only cache binaries when necessary

I find many of the CI minutes are wasted on unnecessary caching

Author: haoqunjiang

.github/workflows/ci.yml

@@ -131,15 +131,17 @@ jobs:
           echo "PLAYWRIGHT_BROWSERS_PATH=$HOME\.cache\playwright-bin" >> $env:GITHUB_ENV
           echo "CYPRESS_CACHE_FOLDER=$HOME\.cache\cypress-bin" >> $env:GITHUB_ENV
 
-      - name: Cache Cypress binaries
+      - if: ${{ contains(matrix.flag-for-e2e, '--cypress') }}
+        name: Cache Cypress binaries
         id: cache-cypress
         uses: actions/cache@v3
         with:
           # TODO: avoid snowballing by adding version
           key: ${{ runner.os }}-cypress-bin
           path: ${{ env.CYPRESS_CACHE_FOLDER }}
 
-      - name: Cache Playwright's binary
+      - if: ${{ contains(matrix.flag-for-e2e, '--playwright') }}
+        name: Cache Playwright's binary
         uses: actions/cache@v3
         with:
           # Playwright removes unused browsers automatically