Add some helm chart unit tests and fix spark service account render failure when extra annotations are specified

[ChenYi015]

• Add some helm chart unit tests
• Close helm chart failed to render spark service account when extra annotations are specified #1966
• Update developer guide about how to setup git pre-commit hooks and developing with helm chart

[vara-bonthu]

@ChenYi015, could you provide further details on the execution process of these unit tests? Also, could you verify whether you've conducted tests on these modifications using the Helm chart?

[ChenYi015]

@ChenYi015, could you provide further details on the execution process of these unit tests? Also, could you verify whether you've conducted tests on these modifications using the Helm chart?

Detailed information about how to run helm chart unit tests can be found here helm-unittest/helm-unittest. First, you need to install helm unit test plugin:

helm plugin install https://github.com/helm-unittest/helm-unittest.git

Then, run helm chart unitt tests as follows:

$ helm unittest charts/spark-operator-chart --strict

### Chart [ spark-operator ] charts/spark-operator-chart

 PASS  Test spark operator deployment   charts/spark-operator-chart/tests/deployment_test.yaml
 PASS  Test spark operator rbac charts/spark-operator-chart/tests/rbac_test.yaml
 PASS  Test spark operator service account      charts/spark-operator-chart/tests/serviceaccount_test.yaml
 PASS  Test spark rbac  charts/spark-operator-chart/tests/spark-rbac_test.yaml
 PASS  Test spark service account       charts/spark-operator-chart/tests/spark-serviceaccount_test.yaml
 PASS  Test spark operator webhook service      charts/spark-operator-chart/tests/webhook-service_test.yaml

Charts:      1 passed, 1 total
Test Suites: 6 passed, 6 total
Tests:       46 passed, 46 total
Snapshot:    0 passed, 0 total
Time:        150.450791ms

It will search for test files under charts/spark-operator-chart/tests directory with suffix _test.yaml and run the test suites.

[ChenYi015]

I have conducted tests on the modifications with my own k8s cluster, and it works as expected.

[vara-bonthu]

Thanks @ChenYi015 ! It would be nice to add this to our contributors.md doc

[vara-bonthu]

/approve

[ChenYi015]

@vara-bonthu I have updated the developer guide about how to setup git pre-commit hooks and developing with helm chart.

[vara-bonthu]

@ChenYi015 one more change required

[vara-bonthu]

nit: spelling "Develop"

[ChenYi015]

updated

[vara-bonthu]

/lgtm

[google-oss-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: ChenYi015, vara-bonthu

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [vara-bonthu]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment