fix(mjpegclient): strip leading space from digest parameter keys

[MichaIng]

After splitting parameters key-value pairs by comma, they have a leading space. It remains as part of the key in the resulting dictionary, breaking utils.build_digest_header().

This change strips spaces from each key-value pair before creating the dictionary.

Before:

dict: {'realm': 'Motion', ' qop': 'auth', ' algorithm': 'MD5', ' nonce': '7c1781f7ebe05a8eb69d3f333038702b000000000888', ' opaque': '025f5245013b0a6c'}

After:

dict: {'realm': 'Motion', 'qop': 'auth', 'algorithm': 'MD5', 'nonce': '23878120785322c2082803516d0d70d3000000004954', 'opaque': '00950ecd01493b25'}