add S3_READ_TIMEOUT environment variable (#14952)

config/initializers/paperclip.rb

@@ -62,7 +62,7 @@ if ENV['S3_ENABLED'] == 'true'
     s3_options: {
       signature_version: ENV.fetch('S3_SIGNATURE_VERSION') { 'v4' },
       http_open_timeout: ENV.fetch('S3_OPEN_TIMEOUT'){ '5' }.to_i,
-      http_read_timeout: 5,
+      http_read_timeout: ENV.fetch('S3_READ_TIMEOUT'){ '5' }.to_i,
       http_idle_timeout: 5,
       retry_limit: 0,
     }