Add a property to get allowNonIncrementalDefinition from a materialized view

[yu-iskw]

Is your feature request related to a problem? Please describe.
Currently, the google-cloud-bigquery Python package does not provide a getter and setter for the allowNonIncrementalDefinition property in the Materialized View Definition. This limitation makes it difficult to manage materialized views effectively, especially when users need to toggle this setting based on their requirements.

Describe the solution you'd like
I would like to see the addition of a getter and setter for the allowNonIncrementalDefinition property in the Materialized View Definition class. This would allow users to easily access and modify this property, enhancing the usability of the package.

Describe alternatives you've considered
As an alternative, users can manually modify the underlying API request payloads, but this approach is cumbersome and error-prone. Having a dedicated property in the Python client would streamline the process and improve code readability.

Additional context
For reference, you can find more information about the allowNonIncrementalDefinition property in the BigQuery documentation.

[chalmerlowe]

Closed by PR #2084