Fix HttpsBrowserProxyAcceptanceTest

[pks-1981]

Fix HttpsBrowserProxyAcceptanceTest

Fix \wiremock\src\test\java\com\github\tomakehurst\wiremock\HttpsBrowserProxyAcceptanceTest.java:143: warning: [removal] getProxies() in ProxyConfiguration has been deprecated and marked for removal
proxyConfig.getProxies().add(httpProxy);

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[pks-1981]

@tomakehurst
or just removing that?
Because @disabled("Jetty doesn't yet support proxying via HTTP2")

[oleg-nenashev]

Thanks!