[REMS-268] Fix Porter

[kennyEung]

• Added 'schemaVersion' to porter.yml as required by breaking changes from the porter v0 to v1 release.

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[kennyEung]

@smalho01 Looking into it further, only the invocationImage field has been deprecated. Not the invocation image or creation of that image.

In otherwords, if our porter.yaml file had defined invocationImage: exampleTag, then we'd get a caution from Porter's linter stating: WARNING: The "invocationImage" field has been deprecated and can no longer be user-specified; ignoring. In which case we'd just have to delete the invocationImage field and its value. It also doesn't seem like we directly reference the invocation image's name anywhere in the workflow CI or CD files. So the pipelines should be good to go.

Porter Migration Reference.