* fixes(java/restclient) Force usage of custom converter
Insert custom converter at the beginning of the 'RestClientBuilder' converter list so as not to use default 'MappingJackson2HttpMessageConverter'
Close#20111
* update samples
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Co-authored-by: William Cheng <wing328hk@gmail.com>
* issue-1960: Add nullability annotations to Java generated clients
Motivations:
Have generated clients properly annotated for nullability to be able to check code using them with tools like NullAway
Modifications:
* Add nullable_var_annotations template to handle nullability annotation on vars
* Add pojo templates to use the nullability template
* Adapt tests
* issue-1960: Add nullability annotations to Java generated clients
Modifications:
* Run export_docs_generator.sh script to update samples
* feat (JAVA SPRING RESTCLIENT) 19406: Add single request parameter for Spring RestClient
Closes#19406
* chore (JAVA SPRING RESTCLIENT) 19406: Add new sample to jdk 17 tests
* fix (JAVA SPRING RESTCLIENT) 19406: Fix sample build