Add CI build using Github Action

[lyang]

I'd like to add CI build using GitHub Action, so that we can fix the build status badge in README.md.

Adding the build itself is straight forward. However, the build seems stuck on one particular test:

    @Test
    public void should_proxy_with_request_method() throws Exception {
        server.get(by(uri("/target"))).response("get_proxy");
        server.post(and(by(uri("/target")), by("proxy"))).response("post_proxy");
        server.request(and(by(uri("/target")), by(method("put")), by("proxy"))).response("put_proxy");
        server.request(and(by(uri("/target")), by(method("delete")))).response("delete_proxy");
        server.request(and(by(uri("/target")), by(method("head")))).response(status(200));
        server.request(and(by(uri("/target")), by(method("options")))).response("options_proxy");
        server.request(and(by(uri("/target")), by(method("trace")))).response("trace_proxy");

        server.request(by(uri("/proxy"))).response(proxy(remoteUrl("/target")));

        running(server, () -> {
            assertThat(helper.get(remoteUrl("/proxy")), is("get_proxy"));
            assertThat(helper.postContent(remoteUrl("/proxy"), "proxy"), is("post_proxy"));

            Request putRequest = Request.put(remoteUrl("/proxy")).bodyString("proxy", ContentType.DEFAULT_TEXT);
            assertThat(helper.executeAsString(putRequest), is("put_proxy"));

            Request deleteRequest = Request.delete(remoteUrl("/proxy"));
            assertThat(helper.executeAsString(deleteRequest), is("delete_proxy"));

            Request headRequest = Request.head(remoteUrl("/proxy"));
            int code = helper.execute(headRequest).getCode();
            assertThat(code, is(200));

            Request optionsRequest = Request.options(remoteUrl("/proxy"));
            assertThat(helper.executeAsString(optionsRequest), is("options_proxy"));

            Request traceRequest = Request.trace(remoteUrl("/proxy"));
            assertThat(helper.executeAsString(traceRequest), is("trace_proxy"));
        });
    }

While the test passes locally with no issue, it hangs on one of the PUT / DELETE / HEAD / OPTIONS / TRACE. The test passes on CI, if only one of the above was executed. Any combination of two (or more) causes the build to hang.

I wasn't able to get to the bottom of cause, but I suspect it has to do with resource releasing.

I refactored the test to use @ParameterizedTest to both help passing the build and remove some code duplication in the test. And effectively added PATCH under test as well. However it does introduce a new test dependency: org.junit.jupiter:junit-jupiter-params.