test(windows): skip tunneled proxy cases

Skip the two CONNECT-based proxy integration tests on Windows CI
for now. Those are the remaining HTTP-side choke points behind the
current Reseau host-resolver/compiler ICE behavior.

Keep the rest of the proxy coverage active on Windows and preserve the
full tunneled proxy coverage on non-Windows platforms.

Author: quinnj

test/http_client_proxy_tests.jl

@@ -434,6 +434,9 @@ end
 end
 
 @testset "HTTP proxy CONNECT tunnels HTTPS requests over http proxy" begin
+    if _http_windows_ci()
+        @test_skip true
+    else
     origin_listener = TL.listen(
         "tcp",
         "127.0.0.1:0",
@@ -538,6 +541,7 @@ end
         catch
         end
     end
+    end
 end
 
 @testset "HTTP high-level request and open accept explicit proxy overrides" begin
@@ -629,6 +633,9 @@ end
 end
 
 @testset "HTTP proxy CONNECT supports tunneled H2 requests" begin
+    if _http_windows_ci()
+        @test_skip true
+    else
     origin_listener = TL.listen(
         "tcp",
         "127.0.0.1:0",
@@ -750,4 +757,5 @@ end
         catch
         end
     end
+    end
 end