* [xdoctest] reformat example code for paddle.jit.api

* test=docs_preview

* add some ... for decorator

* skip some example, test=docs_preview

* add ..., test=docs_preview

* skip some test, test=docs_preview

* more jit files, test=docs_preview

* remove some empty lines, test=docs_preview

* format program translator, test=docs_preview

* remove a blank line, test=docs_preview

* skip translated layer.program, test=docs_preview

* fix doc format, test=docs_preview