Remove `gptsan_japanese` from doctest list to avoid GPU OOM (#21722)

remove from doctest list to avoid GPU OOM
Co-authored-by: ydshieh <ydshieh@users.noreply.github.com>

utils/documentation_tests.txt

@@ -92,7 +92,6 @@ src/transformers/models/glpn/modeling_glpn.py
 src/transformers/models/gpt2/configuration_gpt2.py
 src/transformers/models/gpt2/modeling_gpt2.py
 src/transformers/models/gptj/modeling_gptj.py
-src/transformers/models/gptsan_japanese/modeling_gptsan_japanese.py
 src/transformers/models/gpt_neo/configuration_gpt_neo.py
 src/transformers/models/gpt_neox/configuration_gpt_neox.py
 src/transformers/models/gpt_neox_japanese/configuration_gpt_neox_japanese.py