fix(storage-gcs): return 404 on file not found instead of 500 (#11746)

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Fixes #

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### What?
In a similar vein to #11734, #11733, #10327 - this PR returns a 404 in
the response when a file is not found while using the `storage-gcs`
adapter. Currently a 500 is returned.

### Why?
To return the correct error level in the response when a file is not
found when using `storage-gcs`.

### How?
The GCS nodejs library exposes the `ApiError` as a general error - these
changes check that the caught error is an instance of this class and if
the provided code is a `404`.

packages/storage-gcs/src/staticHandler.ts

@@ -1,7 +1,7 @@
-import type { Storage } from '@google-cloud/storage'
 import type { StaticHandler } from '@payloadcms/plugin-cloud-storage/types'
 import type { CollectionConfig } from 'payload'
 
+import { ApiError, type Storage } from '@google-cloud/storage'
 import { getFilePrefix } from '@payloadcms/plugin-cloud-storage/utilities'
 import path from 'path'
 
@@ -58,6 +58,9 @@ export const getHandler = ({ bucket, collection, getStorageClient }: Args): Stat
         status: 200,
       })
     } catch (err: unknown) {
+      if (err instanceof ApiError && err.code === 404) {
+        return new Response(null, { status: 404, statusText: 'Not Found' })
+      }
       req.payload.logger.error(err)
       return new Response('Internal Server Error', { status: 500 })
     }