Fix/ci container manual start (#20)

Co-authored-by: moilanik <niko.moilanen@tietoevry.com>
Reviewed-on: #20

tests/helpers/mock-api.sh

@@ -24,6 +24,14 @@ _wait_port_free() {
   done
 }
 
+_wait_port_ready() {
+  local i=0
+  while ! lsof -ti ":$MOCK_PORT" >/dev/null 2>&1 && [ $i -lt 5 ]; do
+    sleep 0.2
+    i=$((i + 1))
+  done
+}
+
 mock_set_sequence() {
   MOCK_SEQUENCE_FILE=$(mktemp)
   echo "$1" | jq -c '.' > "$MOCK_SEQUENCE_FILE"
@@ -55,7 +63,7 @@ mock_start() {
   nohup python3 "$(dirname "${BASH_SOURCE[0]}")/mock-server.py" "$MOCK_PORT" "$MOCK_CONFIG_FILE" "$MOCK_REQUEST_FILE" \
     </dev/null >/dev/null 2>&1 &
   MOCK_PID=$!
-  sleep 1
+  _wait_port_ready
 }
 
 mock_stop() {