Add smoketests for UC4

theodolite-benchmarks/docker-test/uc4-beam-flink/test.sh

+#!/bin/sh
+
+docker-compose exec -T kcat kcat -C -b kafka:9092 -t output -s key=s -s value=avro -r http://schema-registry:8081 -f '%k:%s\n' -c 2000 |
+    tee /dev/stderr |
+    awk -F ':' '!/^%/ {print $1}' |
+    sort |
+    uniq |
+    wc -l |
+    grep "\b21\b"

theodolite-benchmarks/docker-test/uc4-beam-samza/test.sh

+#!/bin/sh
+
+docker-compose exec -T kcat kcat -C -b kafka:9092 -t output -s key=s -s value=avro -r http://schema-registry:8081 -f '%k:%s\n' -c 2000 |
+    tee /dev/stderr |
+    awk -F ':' '!/^%/ {print $1}' |
+    sort |
+    uniq |
+    wc -l |
+    grep "\b21\b"

theodolite-benchmarks/docker-test/uc4-flink/test.sh

+#!/bin/sh
+
+docker-compose exec -T kcat kcat -C -b kafka:9092 -t output -s key=s -s value=avro -r http://schema-registry:8081 -f '%k:%s\n' -c 500 |
+    tee /dev/stderr |
+    awk -F ':' '!/^%/ {print $1}' |
+    sort |
+    uniq |
+    wc -l |
+    grep "\b21\b"

theodolite-benchmarks/docker-test/uc4-kstreams/test.sh

+#!/bin/sh
+
+docker-compose exec -T kcat kcat -C -b kafka:9092 -t output -s key=s -s value=avro -r http://schema-registry:8081 -f '%k:%s\n' -c 32 |
+    tee /dev/stderr |
+    awk -F ':' '!/^%/ {print $1}' |
+    sort |
+    uniq |
+    wc -l |
+    grep "\b16\b"