python3Packages.uvloop: disable problematic test on aarch64

This test case gets stuck on our aarch64 builder since the 0.15.0
upgrade, and so the package has not been in the cache for aarch64,
since the job reliably timed out.

The issue didn't get noticed earlier because the package does in fact
build on some aarch64 machines, like my raspberry pi 4.

Reported upstream at MagicStack/uvloop#412.

pkgs/development/python-modules/uvloop/default.nix

@@ -44,8 +44,15 @@ buildPythonPackage rec {
     "--assert=plain"
     "--strict"
     "--tb=native"
+  ] ++ lib.optionals (stdenv.isAarch64) [
+    # test gets stuck in epoll_pwait on hydras aarch64 builders
+    # https://github.com/MagicStack/uvloop/issues/412
+    "--deselect" "tests/test_tcp.py::Test_AIO_TCPSSL::test_remote_shutdown_receives_trailing_data"
+  ];
+
+  disabledTestPaths = [
     # ignore code linting tests
-    "--ignore=tests/test_sourcecode.py"
+    "tests/test_sourcecode.py"
   ];
 
   # force using installed/compiled uvloop vs source by moving tests to temp dir