Ingress port number type conversion issue

[yorinasub17]

Description

This PR fixes a bug where the number type checking for ingress port expression isn't good enough when passing through a number with values.yaml. helm seems to coerce numbers into strings when going through a values.yaml file, which doesn't happen when using --set.

This PR also adds a regression test to make sure we test the path with values.yaml.

Additional note

The regression test expectedly fails without the fix in adc8373 (see build https://app.circleci.com/pipelines/github/gruntwork-io/helm-kubernetes-services/343/workflows/8e969b8a-2c9e-4b1f-819d-e15fb52ff958), but passes after the fix (see https://app.circleci.com/pipelines/github/gruntwork-io/helm-kubernetes-services/344/workflows/a0eeb12e-f372-4005-894b-0e54d3843364)

TODOs

Please ensure all of these TODOs are completed before asking for a review.

• Ensure the branch is named correctly with the issue number. e.g: feature/new-vpc-endpoints-955 or bug/missing-count-param-434.
• Update the docs.
• Keep the changes backward compatible where possible.
• Run the pre-commit checks successfully.
• Run the relevant tests successfully.

[autero1]

LGTM!

[yorinasub17]

Thanks for review! Merging now.