shut down HTTPClient in example (#4)

* HTTPClient needs to be shutdown after use to avoid memory leak

See https://github.com/swift-server/async-http-client/blob/main/README.md#request-response-api

* need to shutdown the HTTPClient before each exit call

Not really recommended programming, but it is to demonstrate the shutdown of the HTTPClient before terminating the program.

* use defer to shutdown the HTTPClient

* http client shutdown in example

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Co-authored-by: Simon Leeb <52261246+sliemeobn@users.noreply.github.com>

Increased maxResponseBytes to avoid NIOTooManyBytesError (#1)

* Increased maxBytes to avoid NIOTooManyBytesError

Calling getPrinterAttributes to request "printer-description", "job-template" and "media-col-database" (as per example at https://www.pwg.org/ipp/ippguide.html#querying-the-printer-attributes ) on Simulated InkJet results in an NIOTooManyBytesError. Raised the hardcoded max value to 1 MB instead of 20 KB and made it an optional param.

* Renamed maxBytes

Renamed maxBytes to maxResponseBytes

add .spi.yaml