[Addon] velaux allow a custom ingress class name

[oanasc]

Description of your changes

Fixes ##739

How has this code been tested?

Enabled the modified addon locally and ensured I can specify the gatewayDriver with a custom name and that is correctly used in the ingressClass annotation the ingress works.

Checklist

I have:

• Title of the PR starts with type (e.g. [Addon] , [example] or [Doc]).
• Updated/Added any relevant documentation and examples.
• New addon should be put in experimental.
• Update addon should modify the version in metadata.yaml to generate a new version.

Verified Addon promotion rules

If this pr wants to promote an experimental addon to verified, you must check whether meet these conditions too:

• This addon must be tested by addon's e2e-test to guarantee this addon can be enabled successfully.
• This addon must have some basic but necessary information.
  • An accessible icon url and source url defined in addon's metadata.yaml.
  • A detail introduction include a basic example about how to use and what's the benefit of this addon in README.md.
  • Also provide an introduction in KubeVela documentation.
  • It's more likely to be accepted if useful examples provided in example dir.

[wonderflow]

maybe you can reuse the gatewayDriver field.

[oanasc]

Noted, updated to use gatewayDriver and works on my cluser. The e2e test however is timing out, seeing why

[oanasc]

Tests are failing because the version of the addon is also used for the image tag, do you prefer creating a new tag v1.9.4 or parameterising the image tag and allow for addons upgrades independently from velaux

[oanasc]

@charlie0129 what do you think. I get is nice for the tag/version of addon to map but in reality there can be addon changes with not image release