Pipeline tests for jitter & dynamic latency

[baranovmv]

1. smoke test: automatic latency works (e.g.: enable latency tuning, run receiver for a while, check that niq latency is close to target; increase jitter, check that after a while niq latency is close to new target; decrease jitter, check; repeat a few times)

   it would be also great to add same test, but with automatic latency disabled, and check that niq latency stays close to target no matter what is the jitter

2. smoke test: start latency works (set start latency different from target and see how niq latency starts with start_latency and goes to target)

3. smoke test: min/max latency works (bounding of target latency)

4. smoke test: jitter metric calculation

   roc-toolkit/src/tests/roc_pipeline/test_receiver_source.cpp

   Lines 3567 to 3570 in 987f5e3

   	// Check how receiver computes jitter metric.
   	IGNORE_TEST(receiver_source, metrics_jitter) {
   	// TODO(gh-688): implement test
   	}