perf: optimize parseCspHeaders (#29887)

* fix: optimize parseCspHeaders

* Added changelog notes

* Fix changelog

---------

Co-authored-by: Jennifer Shehane <[email protected]>

Author: Connormiha

cli/CHANGELOG.md

@@ -3,6 +3,10 @@
 
 _Released 7/30/2024 (PENDING)_
 
+**Performance:**
+
+- Improved performance of `reduce` in a method within our proxy. Addressed in [#29887](https://github.com/cypress-io/cypress/pull/29887).
+
 **Bugfixes:**
 
 - Fixed an issue where yarn PnP was not working correctly with Cypress and `@cypress/webpack-batteries-included-preprocessor`. Fixes [#27947](https://github.com/cypress-io/cypress/issues/27947).

packages/proxy/lib/http/util/csp-header.ts

@@ -107,7 +107,9 @@ export function parseCspHeaders (headers: OutgoingHttpHeaders, headerName: strin
       policy = cspRegExp.exec(cspHeader)
     }
 
-    return [...acc, policies]
+    acc.push(policies)
+
+    return acc
   }, [])
 }