fix command for running shares bats tests

Author: Olesja Aarma

test/README.md

@@ -64,6 +64,7 @@ To use pre-built images, login to docker (ghcr.io) - [Authenticating with person
 Run `cdoc2_shares_server_tests.bats` tests with following command:
 ```bash
 cd bats
+source ../config/shares-server/export-env.sh ../config/shares-server/.env.cyber
 bash run-shares-server-bats-tests.sh
 ```