fix(dart): use qs_dart for HTTP query encoding in DioRequester

[techouse]

🧭 What and Why

Use qs_dart to encode the HTTP query in DioRequester.

Why? I think that using a naive approach like

api-clients-automation/clients/algoliasearch-client-dart/packages/client_core/lib/src/transport/dio/dio_requester.dart

Line 104 in 0052b1f

"${uri.toString()}?${request.queryParameters.entries.map((e) => "${e.key}=${e.value}").join("&")}");

is not exhaustive enough.

Changes included:

• change DioRequester.requestUri method

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Full disclosure: I am the author of qs_dart which is itself is a port of qs.
qs_dart has extensive tests and has been used in Chopper since v7.4.0.