Fix: fix pnpm --allow-build command example to actually work as is. (#6201)

Author: kahlstrm

docs/app/get-started/install-cypress.mdx

@@ -175,7 +175,7 @@ Refer to the [pnpm settings](https://pnpm.io/settings) documentation for additio
 In [pnpm@10.4.0](https://github.com/pnpm/pnpm/releases/tag/v10.4.0) and above, the CLI `add` option [--allow-build](https://pnpm.io/cli/add#--allow-build) can be used, for example:
 
 ```shell
-pnpm --allow-build cypress add --save-dev cypress
+pnpm --allow-build=cypress add --save-dev cypress
 ```
 
 ### Hardware