Scale down cypress CI workers (streamlit#8445)

## Describe your changes

We have migrated another big chunk of Cypress tests to Playwright.
Allowing us to scale down the number of workers by four.

---

**Contribution License Agreement**

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project are made under the Apache 2.0 license.

.github/workflows/cypress.yml

@@ -33,7 +33,7 @@ jobs:
         # Be aware that specs should be sequential integers starting from 1 without gaps
         # based on logic in "Cypress Tests" step.
         # prettier-ignore
-        specs: [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ]
+        specs: [ 1, 2, 3, 4, 5, 6, ]
 
     steps:
       - name: Checkout Streamlit code
@@ -75,7 +75,7 @@ jobs:
         env:
           CURRENT_RUN: ${{matrix.specs}}
           CYPRESS_VERIFY_TIMEOUT: 90000
-          TOTAL_WORKERS: 10
+          TOTAL_WORKERS: 6
         run: |
           js_specs=(e2e/specs/*)