[BUG] Azure-Core cannot encode with some character in query param

[ChenTanyi]

Describe the bug
Azure-Core cannot encode with some character in query param like $, /

To Reproduce
Steps to reproduce the behavior:
run the following code, it will request with http://httpbin.org/get?$filter=a/b

Code Snippet

public class App {
    public static void main(String[] args) {
        try {
            HttpClient client = new NettyAsyncHttpClientBuilder().build();
            Service proxy = RestProxy.create(Service.class, new HttpPipelineBuilder().policies(new UrlPolicy()).httpClient(client).build());

            proxy.get("http://httpbin.org/", "a/b")
                    .doOnNext(System.out::println)
                    .block();

        } catch (Exception e) {
            System.out.println(e.getMessage());
            e.printStackTrace();
        }
    }


    @Host("{$host}")
    @ServiceInterface(name = "Service")
    private interface Service {
        @Get("/get")
        Mono<Map<String, Object>> get(@HostParam("$host") String host, @QueryParam("$filter") String filter);
    }

    private static class UrlPolicy implements HttpPipelinePolicy {

        @Override
        public Mono<HttpResponse> process(HttpPipelineCallContext context, HttpPipelineNextPolicy next) {
            System.out.println(context.getHttpRequest().getUrl());
            return next.process();
        }
    }
}

Expected behavior
It should request with http://httpbin.org/get?%24filter=a%2Fb instead.

Setup (please complete the following information):

• OS: Windows 10
• IDE : Java 1.8.0_231
• Version of the Library used
  • Azure-core, Azure-core-http-netty 1.5.0

Information Checklist
Kindly make sure that you have added all the following information above and checkoff the required fields otherwise we will treat the issuer as an incomplete report

• Bug Description Added
• Repro Steps Added
• Setup information Added

[YijunXieMS]

@ChenTanyi
'/' and '?' can be used in query param values according to RFC 3986. Please refer to this stackoverflow post

Azure core doesn't encode query param names ("$filter" in you example) because we assume no azure service uses a param name that has a space that breaks. Unencoded "$" in param name should work.
Are you aware of any problems caused by this encoding design?

[ChenTanyi]

@YijunXieMS Yes, in the PR I mentioned above. The azure SQL database listMetrics will fail due to the encoding. You could see the code sample in https://github.com/azure/azure-sdk-for-java/blob/4bb437c58cdf2c7645fa6932862507c931d47b21/sdk/resourcemanager/azure-resourcemanager-samples/src/main/java/com/azure/resourcemanager/sql/samples/GettingSqlServerMetrics.java#L199 while the track 1 code with encoding will succeed.

[ChenTanyi]

After discussing, the SQL request error is due to the time format instead of encoding. So close it.