Improving test_manifests_collection test output when waiting on data

[gantrior]

There were errors like:

[integration-test-manual-4b4m8] test_manifests_collection.py kubectl run dummy-pod --labels "test-label=test-value" --overrides="{ \"apiVersion\": \"v1\", \"metadata\": {\"annotations\": { \"test-annotation\":\"test-value\" } } }" --image bash:alpine3.19 -n default -- -ec "while :; do sleep 5 ; done"
[integration-test-manual-4b4m8] pod/dummy-pod created
[integration-test-manual-4b4m8] 
[integration-test-manual-4b4m8] 
[integration-test-manual-4b4m8] Error during ClickHouse test: Expecting value: line 1 column 1 (char 0)
[integration-test-manual-4b4m8] Traceback (most recent call last):
[integration-test-manual-4b4m8]   File "/app/test_utils.py", line 23, in retry_until_ok_clickhouse
[integration-test-manual-4b4m8]     result = assert_func(data)
[integration-test-manual-4b4m8]   File "/app/test_manifests_collection.py", line 53, in assert_test_manifest_found
[integration-test-manual-4b4m8]     if is_correct_manifest(manifest, 'Pod', pod_name, namespace_name):
[integration-test-manual-4b4m8]        ~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[integration-test-manual-4b4m8]   File "/app/test_manifests_collection.py", line 122, in is_correct_manifest
[integration-test-manual-4b4m8]     parsed_manifest = json.loads(raw_manifest)
[integration-test-manual-4b4m8]   File "/usr/local/lib/python3.13/json/__init__.py", line 346, in loads
[integration-test-manual-4b4m8]     return _default_decoder.decode(s)
[integration-test-manual-4b4m8]            ~~~~~~~~~~~~~~~~~~~~~~~^^^
[integration-test-manual-4b4m8]   File "/usr/local/lib/python3.13/json/decoder.py", line 345, in decode
[integration-test-manual-4b4m8]     obj, end = self.raw_decode(s, idx=_w(s, 0).end())
[integration-test-manual-4b4m8]                ~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^
[integration-test-manual-4b4m8]   File "/usr/local/lib/python3.13/json/decoder.py", line 363, in raw_decode
[integration-test-manual-4b4m8]     raise JSONDecodeError("Expecting value", s, err.value) from None
[integration-test-manual-4b4m8] json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)
[integration-test-manual-4b4m8] 

it should be fixed now