text: Title: Scrapy does not decode base64 MD5 checksum from GCS
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  ### Description
  
  Incorrect GCS Checksum processing
  
  ### Steps to Reproduce
  
  1. Obtain the checksum for an up-to-date file.
  
  **Expected behavior:** [What you expect to happen]
  matches the checksum of the file downloaded
  **Actual behavior:** [What actually happens]
  NOT matches the checksum of the file downloaded
  **Reproduces how often:** [What percentage of the time does it reproduce?]
  Always
  ### Versions
  current
  
  ### Additional context
  
  https://cloud.google.com/storage/docs/json_api/v1/objects
  > MD5 hash of the data, encoded using [base64](https://datatracker.ietf.org/doc/html/rfc4648#section-4).
  
  But, Scrapy dose not decode MD5 from GCS.
  