doc: add README for tests

Signed-off-by: Lenin Mehedy <lenin.mehedy@swirldslabs.com>

charts/hedera-network/tests/README.md

@@ -0,0 +1,20 @@
+# Helm Chart Tests
+This directory contains the BATS tests for helm chart. 
+
+`run.sh` is the entrypoint to execute the tests locally assuming
+you have the network deployed already.
+
+## Development
+Use the `test_basic_deployment.bats` file as the template while creating new tests.
+
+## Run
+- First create a .env file in this directory from the `env.template` file
+- From `dev` folder run `make deploy-network`
+- Once network is deployed, you can run `./run.sh` to run the tests.
+- When tests are working, then redeploy and run the helm tests: `make destroy-network deploy-network helm-test`
+
+## Notes
+- Any new template variables should be added in `helpers.sh` with prefix `TMPL_` (e.g TMPL_TOTAL_NODES)  
+- Any new required env variable should be added in `env.sh`
+- Any new helper function should be added in `helpers.sh`
+- If a new script file is added, load it in `load.sh`