[FEATURE] "lombok.addNullAnnotations" support for jspecify

[zman0900]

Describe the feature
The configuration option lombok.addNullAnnotations already supports adding a wide variety of nullness annotations to generated code. Please add support the the JSpecify annotations also so that they don't have to be configured as custom.

I have not included code snippets here since I believe this would generate identical code to what is generated for other nullness annotations that allow type-use, such as checkerframework.

Describe the target audience
Users of JSpecify annotations.

Additional context
Lombok already supports JSpecify as copyable annotations in #3608. This would complete that support.