Unifies naming for isArray in Schema class properties

[spacether]

We are using multiple properties that mean this schema is type array. The properties are:

• isListContainer
• isArrayModel

This PR updates our java classes that implement Schema to be consistent in out naming and getters and setters for this property. These classes have been updated:

• CodegenProperty
• CodegenModel
• CodegenParameter
• CodegenResponse

This PR:

• changes isListContainer + isArrayModel to isArray
• is a feature break out for [REQ] Implement needed common isX properties in java Schema classes in openapi core #7651

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