Missing cloud config options from CAPI Helm Schema

[JasleenKaurSethi]

Fix cloudConfig schema validation for values already supported by the cloud-config.yaml template.

The template supports some fields that the schema is missing causing Magnum CAPI Helm installs to fail when passing valid cloud config options.

Thus,

• Added explicitly templated options to the schema
• additionalProperties true is set for fields which allow additional fields

[wtripp180901]

Would be good to test the new fields by adding them to values_full.yaml, where that is possible.

Also these changes get overwritten when running helm schema, I think you can pass information for maps which don't have defaults set in values.yaml by defining them in schema annotations e.g

# @schema
# type: [object, "null"]
# properties:
#   host:
#     type: string
#   port:
#     type: integer
# @schema
myField: