[Rust] Remove `BufferBuilderTrait` and associated Result requirement.

[asfimport]

The trait is no longer used, as we completely split the build of boolean and non-boolean buffers, and the purpose of that trait was to support multiple implementations of the buffer building.

 

This trait also has Result for infallible methods.

Reporter: Jorge Leitão / @jorgecarleitao
Assignee: Jorge Leitão / @jorgecarleitao

PRs and other links:

• GitHub Pull Request #9017

_{Note: This issue was originally created as ARROW-11038. Please see the migration documentation for further details.}

[asfimport]

Andrew Lamb / @alamb:
Issue resolved by pull request 9017
#9017