check.gst-editing-services.nle_simple.test_simplest sometimes fails

CI log: https://gitlab.freedesktop.org/alatiera/gst-ci/-/jobs/77359

Output

check.gst-editing-services.nle_simple.test_simplest: Failed 'Application returned 1'
       You can reproduce with: GST_CHECKS='test_simplest' GST_REGISTRY='/builds/alatiera/gst-ci/gst-build/build/subprojects/gst-editing-services/tests/check/nle_simple.registry' GST_STATE_IGNORE_ELEMENTS='' GST_PLUGIN_PATH_1_0='/builds/alatiera/gst-ci/gst-build/build' GST_PLUGIN_SYSTEM_PATH_1_0='' CK_DEFAULT_TIMEOUT='20' /builds/alatiera/gst-ci/gst-build/build/subprojects/gst-editing-services/tests/check/nle_simple

Dumping log files on failure

Dumping contents of /builds/alatiera/gst-ci/validate-output/logs/check/gst-editing-services/nle_simple/test_simplest

=================
Test name: check.gst-editing-services.nle_simple.test_simplest
Command: '/builds/alatiera/gst-ci/gst-build/build/subprojects/gst-editing-services/tests/check/nle_simple'
=================

Running suite(s): gnonlin-simple
0:00:00.086976807 15890      0x166e560 ERROR                  check simple.c:63:test_simplest_full: Setting pipeline to PLAYING
0:00:00.190845613 15890      0x166e560 ERROR                  check simple.c:80:test_simplest_full: Resetted pipeline to READY
0:00:00.190858968 15890      0x166e560 ERROR                  check simple.c:88:test_simplest_full: Setting pipeline to PLAYING again
0%: Checks: 1, Failures: 1, Errors: 0
../subprojects/gstreamer/libs/gst/check/gstcheck.c:1235:F:general:test_simplest:0: source1_0x161a5a0 is not destroyed, 1 refcounts left!
Check suite gnonlin ran in 0.155s (tests failed: 1)