ci: fix iast_memcheck flakyness [backport 2.9] (#10154) #54601

Job	Run time
test_unit (dd-lib-python-init-test-django)	3m 22s
test_unit (dd-lib-python-init-test-django-gunicorn)	3m 19s
test_unit (dd-lib-python-init-test-django-gunicorn-alpine)	3m 16s
test_unit (dd-lib-python-init-test-django-uvicorn)	3m 24s
test_unit (dd-lib-python-init-test-django-no-perms)	3m 24s
test_unit (dd-lib-python-init-test-django-pre-installed)	3m 46s
test_unit (dd-lib-python-init-test-django-unsupported-python)	3m 42s
build-and-publish-test-image / wait_for_package	7s
build-and-publish-test-image / build_push / build_push	13m 29s
test-runner-test (dd-lib-python-init-test-django)	3m 3s
test-runner-test (dd-lib-python-init-test-django-gunicorn)	3m 8s
test-runner-test (dd-lib-python-init-test-django-uvicorn)	3m 1s
	47m 1s

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